diff --git a/src/components/process-management/ProcessDetail.tsx b/src/components/process-management/ProcessDetail.tsx
index 0c4196e6..bd5866f2 100644
--- a/src/components/process-management/ProcessDetail.tsx
+++ b/src/components/process-management/ProcessDetail.tsx
@@ -11,7 +11,7 @@
 
 import { useState, useEffect, useCallback, useRef } from 'react';
 import { useRouter } from 'next/navigation';
-import { ArrowLeft, Copy, Edit, GripVertical, Plus, Trash2 } from 'lucide-react';
+import { ArrowLeft, Copy, Edit, GripVertical, Plus, Trash2, ExternalLink } from 'lucide-react';
 import { ReorderButtons } from '@/components/molecules';
 import { Button } from '@/components/ui/button';
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
@@ -229,8 +229,23 @@ export function ProcessDetail({ process, onProcessUpdate }: ProcessDetailProps)
                 <div className="font-medium">{process.manager || '-'}</div>
               </div>
             </div>
-            {/* Row 2: 구분 | 생산일자 | 상태 */}
+            {/* Row 2: 부모공정 | 구분 | 생산일자 | 상태 */}
             <div className="grid grid-cols-2 lg:grid-cols-4 gap-4 md:gap-6 mt-4 md:mt-6">
+              <div className="space-y-1">
+                <div className="text-sm text-muted-foreground">부모 공정</div>
+                {process.parentId ? (
+                  <button
+                    type="button"
+                    onClick={() => router.push(`/ko/master-data/process-management/${process.parentId}?mode=view`)}
+                    className="font-medium text-primary hover:underline flex items-center gap-1"
+                  >
+                    [{process.parentProcessCode}] {process.parentProcessName}
+                    <ExternalLink className="h-3 w-3" />
+                  </button>
+                ) : (
+                  <div className="font-medium text-muted-foreground">없음 (루트 공정)</div>
+                )}
+              </div>
               <div className="space-y-1">
                 <div className="text-sm text-muted-foreground">구분</div>
                 <div className="font-medium">{process.processCategory || '없음'}</div>
@@ -278,6 +293,38 @@ export function ProcessDetail({ process, onProcessUpdate }: ProcessDetailProps)
           </CardContent>
         </Card>
 
+        {/* 하위 공정 (자식이 있을 때만 표시) */}
+        {process.children && process.children.length > 0 && (
+          <Card>
+            <CardHeader className="bg-muted/50 py-3">
+              <div className="flex items-center gap-2">
+                <CardTitle className="text-base">하위 공정</CardTitle>
+                <Badge variant="outline" className="text-xs">
+                  {process.children.length}개
+                </Badge>
+              </div>
+            </CardHeader>
+            <CardContent className="p-0">
+              <div className="divide-y">
+                {process.children.map((child) => (
+                  <div
+                    key={child.id}
+                    onClick={() => router.push(`/ko/master-data/process-management/${child.id}?mode=view`)}
+                    className="flex items-center gap-4 px-4 py-3 cursor-pointer hover:bg-muted/50"
+                  >
+                    <span className="text-sm font-mono text-muted-foreground">{child.processCode}</span>
+                    <span className="text-sm font-medium flex-1">{child.processName}</span>
+                    <Badge variant={child.status === '사용중' ? 'default' : 'secondary'} className="text-xs">
+                      {child.status === '사용중' ? '사용' : '미사용'}
+                    </Badge>
+                    <ExternalLink className="h-3.5 w-3.5 text-muted-foreground" />
+                  </div>
+                ))}
+              </div>
+            </CardContent>
+          </Card>
+        )}
+
         {/* 품목 설정 정보 */}
         <Card>
           <CardHeader className="bg-muted/50 py-3">
diff --git a/src/components/process-management/ProcessForm.tsx b/src/components/process-management/ProcessForm.tsx
index f4039182..202ee2bf 100644
--- a/src/components/process-management/ProcessForm.tsx
+++ b/src/components/process-management/ProcessForm.tsx
@@ -40,6 +40,7 @@ import {
   getDepartmentOptions,
   getProcessSteps,
   getDocumentTemplates,
+  getRootProcessOptions,
   type DepartmentOption,
   type DocumentTemplateOption,
 } from './actions';
@@ -53,6 +54,12 @@ export function ProcessForm({ mode, initialData }: ProcessFormProps) {
   const router = useRouter();
   const isEdit = mode === 'edit';
 
+  // 부모 공정 상태
+  const [parentId, setParentId] = useState<number | undefined>(
+    initialData?.parentId ? Number(initialData.parentId) : undefined
+  );
+  const [rootProcessOptions, setRootProcessOptions] = useState<Array<{ id: string; processCode: string; processName: string }>>([]);
+
   // 기본 정보 상태
   const [processName, setProcessName] = useState(initialData?.processName || '');
   const [processType, _setProcessType] = useState<ProcessType>(
@@ -152,18 +159,26 @@ export function ProcessForm({ mode, initialData }: ProcessFormProps) {
     setShowRemoveAllDialog(false);
   }, []);
 
-  // 부서 목록 + 문서양식 목록 로드
+  // 부서 목록 + 문서양식 목록 + 루트 공정 목록 로드
   useEffect(() => {
     const loadInitialData = async () => {
       setIsDepartmentsLoading(true);
-      const [departments, templates] = await Promise.all([
+      const [departments, templates, rootProcesses] = await Promise.all([
         getDepartmentOptions(),
         getDocumentTemplates(),
+        getRootProcessOptions(),
       ]);
       setDepartmentOptions(departments);
       if (templates.success && templates.data) {
         setDocumentTemplates(templates.data);
       }
+      if (rootProcesses.success && rootProcesses.data) {
+        // 수정 모드에서 자기 자신은 제외
+        const filtered = isEdit && initialData?.id
+          ? rootProcesses.data.filter(p => p.id !== initialData.id)
+          : rootProcesses.data;
+        setRootProcessOptions(filtered);
+      }
       setIsDepartmentsLoading(false);
     };
     loadInitialData();
@@ -340,6 +355,7 @@ export function ProcessForm({ mode, initialData }: ProcessFormProps) {
     }
 
     const formData = {
+      parentId: parentId || undefined,
       processName: processName.trim(),
       processType,
       processCategory: processCategory || undefined,
@@ -459,8 +475,28 @@ export function ProcessForm({ mode, initialData }: ProcessFormProps) {
                   />
                 </div>
               </div>
-              {/* Row 2: 구분 | 생산일자 | 상태 */}
+              {/* Row 2: 부모공정 | 구분 | 생산일자 | 상태 */}
               <div className="grid grid-cols-2 lg:grid-cols-4 gap-4 md:gap-6 mt-4 md:mt-6">
+                <div className="space-y-2">
+                  <Label>부모 공정</Label>
+                  <Select
+                    key={`parent-${parentId ?? 'none'}`}
+                    value={parentId ? String(parentId) : 'none'}
+                    onValueChange={(v) => setParentId(v === 'none' ? undefined : Number(v))}
+                  >
+                    <SelectTrigger>
+                      <SelectValue placeholder="없음 (루트 공정)" />
+                    </SelectTrigger>
+                    <SelectContent>
+                      <SelectItem value="none">없음 (루트 공정)</SelectItem>
+                      {rootProcessOptions.map((opt) => (
+                        <SelectItem key={opt.id} value={opt.id}>
+                          [{opt.processCode}] {opt.processName}
+                        </SelectItem>
+                      ))}
+                    </SelectContent>
+                  </Select>
+                </div>
                 <div className="space-y-2">
                   <Label>구분</Label>
                   <Select
@@ -825,6 +861,8 @@ export function ProcessForm({ mode, initialData }: ProcessFormProps) {
       </>
     ),
     [
+      parentId,
+      rootProcessOptions,
       processName,
       processType,
       processCategory,
diff --git a/src/components/process-management/ProcessListClient.tsx b/src/components/process-management/ProcessListClient.tsx
index 1778aa63..65fc9b60 100644
--- a/src/components/process-management/ProcessListClient.tsx
+++ b/src/components/process-management/ProcessListClient.tsx
@@ -12,7 +12,7 @@
 import { useState, useMemo, useCallback, useEffect, useRef } from 'react';
 import { useRouter } from 'next/navigation';
 import { useDateRange } from '@/hooks';
-import { Wrench, Plus, GripVertical } from 'lucide-react';
+import { Wrench, Plus, GripVertical, ChevronRight, ChevronDown } from 'lucide-react';
 import { Button } from '@/components/ui/button';
 import { TableCell, TableRow, TableHead } from '@/components/ui/table';
 import { Checkbox } from '@/components/ui/checkbox';
@@ -51,6 +51,55 @@ export default function ProcessListClient({ initialData = [], initialStats }: Pr
   // 검색어 상태
   const [searchQuery, setSearchQuery] = useState('');
 
+  // 트리 접기/펼치기 상태 (부모 공정 ID → expanded 여부)
+  const [expandedParents, setExpandedParents] = useState<Set<string>>(new Set());
+
+  const toggleExpand = useCallback((parentId: string) => {
+    setExpandedParents(prev => {
+      const next = new Set(prev);
+      if (next.has(parentId)) next.delete(parentId);
+      else next.add(parentId);
+      return next;
+    });
+  }, []);
+
+  // 트리 구조 정렬: 부모 바로 뒤에 자식을 배치
+  const treeOrderedProcesses = useMemo(() => {
+    const childrenMap = new Map<string, Process[]>();
+    const roots: Process[] = [];
+
+    for (const p of allProcesses) {
+      if (p.parentId) {
+        const siblings = childrenMap.get(p.parentId) || [];
+        siblings.push(p);
+        childrenMap.set(p.parentId, siblings);
+      } else {
+        roots.push(p);
+      }
+    }
+
+    const result: Process[] = [];
+    for (const root of roots) {
+      result.push(root);
+      const children = childrenMap.get(root.id) || [];
+      if (children.length > 0 && expandedParents.has(root.id)) {
+        result.push(...children);
+      }
+    }
+    return result;
+  }, [allProcesses, expandedParents]);
+
+  // 초기 로드 시 자식이 있는 부모는 자동 펼침
+  useEffect(() => {
+    const parentsWithChildren = new Set<string>();
+    for (const p of allProcesses) {
+      if (p.parentId) parentsWithChildren.add(p.parentId);
+    }
+    if (parentsWithChildren.size > 0) {
+      setExpandedParents(parentsWithChildren);
+    }
+  }, [allProcesses]);
+
   // 드래그&드롭 순서 변경 상태
   const [isOrderChanged, setIsOrderChanged] = useState(false);
   const dragProcessIdRef = useRef<string | null>(null);
@@ -425,23 +474,26 @@ export default function ProcessListClient({ initialData = [], initialStats }: Pr
         const itemCount = process.classificationRules
           .filter(r => r.registrationType === 'individual')
           .reduce((sum, r) => sum + (r.items?.length || 0), 0);
+        const isChild = !!process.parentId;
+        const hasChildren = allProcesses.some(p => p.parentId === process.id);
+        const isExpanded = expandedParents.has(process.id);
         return (
           <TableRow
             key={process.id}
-            draggable
-            onDragStart={(e) => handleDragStart(e, process.id)}
-            onDragOver={handleDragOver}
-            onDragLeave={handleDragLeave}
-            onDragEnd={handleDragEnd}
-            onDrop={(e) => handleProcessDrop(e, process.id)}
-            className={`cursor-pointer hover:bg-muted/50 ${handlers.isSelected ? 'bg-blue-50' : ''}`}
+            draggable={!isChild}
+            onDragStart={!isChild ? (e) => handleDragStart(e, process.id) : undefined}
+            onDragOver={!isChild ? handleDragOver : undefined}
+            onDragLeave={!isChild ? handleDragLeave : undefined}
+            onDragEnd={!isChild ? handleDragEnd : undefined}
+            onDrop={!isChild ? (e) => handleProcessDrop(e, process.id) : undefined}
+            className={`cursor-pointer hover:bg-muted/50 ${handlers.isSelected ? 'bg-blue-50' : ''} ${isChild ? 'bg-muted/20' : ''}`}
             onClick={() => handleRowClick(process)}
           >
             <TableCell
               className="text-center cursor-grab active:cursor-grabbing"
               onClick={(e) => e.stopPropagation()}
             >
-              <GripVertical className="h-4 w-4 text-muted-foreground mx-auto" />
+              {!isChild && <GripVertical className="h-4 w-4 text-muted-foreground mx-auto" />}
             </TableCell>
             <TableCell className="text-center" onClick={(e) => e.stopPropagation()}>
               <Checkbox
@@ -450,8 +502,31 @@ export default function ProcessListClient({ initialData = [], initialStats }: Pr
               />
             </TableCell>
             <TableCell className="text-center text-muted-foreground">{globalIndex}</TableCell>
-            <TableCell className="font-medium">{process.processCode}</TableCell>
-            <TableCell>{process.processName}</TableCell>
+            <TableCell className="font-medium">
+              {isChild && <span className="text-muted-foreground mr-1">└</span>}
+              {process.processCode}
+            </TableCell>
+            <TableCell>
+              <div className={`flex items-center gap-1 ${isChild ? 'pl-6' : ''}`}>
+                {hasChildren && (
+                  <button
+                    type="button"
+                    onClick={(e) => { e.stopPropagation(); toggleExpand(process.id); }}
+                    className="shrink-0 p-0.5 rounded hover:bg-muted"
+                  >
+                    {isExpanded
+                      ? <ChevronDown className="h-4 w-4 text-muted-foreground" />
+                      : <ChevronRight className="h-4 w-4 text-muted-foreground" />}
+                  </button>
+                )}
+                <span>{process.processName}</span>
+                {hasChildren && (
+                  <Badge variant="outline" className="text-[10px] ml-1">
+                    {allProcesses.filter(p => p.parentId === process.id).length}
+                  </Badge>
+                )}
+              </div>
+            </TableCell>
             <TableCell>{process.department}</TableCell>
             <TableCell className="text-center">{itemCount > 0 ? itemCount : '-'}</TableCell>
             <TableCell className="text-center">
@@ -487,50 +562,53 @@ export default function ProcessListClient({ initialData = [], initialStats }: Pr
         const itemCount = process.classificationRules
           .filter(r => r.registrationType === 'individual')
           .reduce((sum, r) => sum + (r.items?.length || 0), 0);
+        const isChild = !!process.parentId;
         return (
-          <ListMobileCard
-            key={process.id}
-            id={process.id}
-            isSelected={handlers.isSelected}
-            onToggleSelection={handlers.onToggle}
-            onClick={() => handleRowClick(process)}
-            headerBadges={
-              <>
-                <Badge variant="outline" className="text-xs">{globalIndex}</Badge>
-                <Badge variant="outline" className="text-xs font-mono">{process.processCode}</Badge>
-              </>
-            }
-            title={process.processName}
-            statusBadge={
-              <Badge
-                variant={process.status === '사용중' ? 'default' : 'secondary'}
-                className="cursor-pointer"
-                onClick={(e) => {
-                  e.stopPropagation();
-                  handleToggleStatus(process.id);
-                }}
-              >
-                {process.status === '사용중' ? '사용' : '미사용'}
-              </Badge>
-            }
-            infoGrid={
-              <div className="grid grid-cols-2 gap-x-4 gap-y-3">
-                <InfoField label="담당부서" value={process.department} />
-                <InfoField label="품목" value={itemCount > 0 ? `${itemCount}개` : '-'} />
-                <InfoField label="중간검사" value={process.needsInspection ? '사용' : '미사용'} />
-                <InfoField label="작업일지" value={process.needsWorkLog ? '사용' : '미사용'} />
-              </div>
-            }
-          />
+          <div key={process.id} className={isChild ? 'ml-4 border-l-2 border-muted' : ''}>
+            <ListMobileCard
+              id={process.id}
+              isSelected={handlers.isSelected}
+              onToggleSelection={handlers.onToggle}
+              onClick={() => handleRowClick(process)}
+              headerBadges={
+                <>
+                  <Badge variant="outline" className="text-xs">{globalIndex}</Badge>
+                  <Badge variant="outline" className="text-xs font-mono">{process.processCode}</Badge>
+                  {isChild && <Badge variant="secondary" className="text-[10px]">하위</Badge>}
+                </>
+              }
+              title={process.processName}
+              statusBadge={
+                <Badge
+                  variant={process.status === '사용중' ? 'default' : 'secondary'}
+                  className="cursor-pointer"
+                  onClick={(e) => {
+                    e.stopPropagation();
+                    handleToggleStatus(process.id);
+                  }}
+                >
+                  {process.status === '사용중' ? '사용' : '미사용'}
+                </Badge>
+              }
+              infoGrid={
+                <div className="grid grid-cols-2 gap-x-4 gap-y-3">
+                  <InfoField label="담당부서" value={process.department} />
+                  <InfoField label="품목" value={itemCount > 0 ? `${itemCount}개` : '-'} />
+                  <InfoField label="중간검사" value={process.needsInspection ? '사용' : '미사용'} />
+                  <InfoField label="작업일지" value={process.needsWorkLog ? '사용' : '미사용'} />
+                </div>
+              }
+            />
+          </div>
         );
       },
     }),
-    [handleCreate, handleRowClick, handleToggleStatus, handleBulkDelete, startDate, endDate, searchQuery, isOrderChanged, handleSaveOrder, handleDragStart, handleDragOver, handleDragLeave, handleDragEnd, handleProcessDrop]
+    [handleCreate, handleRowClick, handleToggleStatus, handleBulkDelete, startDate, endDate, searchQuery, isOrderChanged, handleSaveOrder, handleDragStart, handleDragOver, handleDragLeave, handleDragEnd, handleProcessDrop, allProcesses, expandedParents, toggleExpand]
   );
 
   return (
     <>
-      <UniversalListPage config={config} initialData={allProcesses} onSearchChange={setSearchQuery} />
+      <UniversalListPage config={config} initialData={treeOrderedProcesses} onSearchChange={setSearchQuery} />
 
       {/* 삭제 확인 다이얼로그 */}
       <DeleteConfirmDialog
diff --git a/src/components/process-management/actions.ts b/src/components/process-management/actions.ts
index 2f780b83..56857ccb 100644
--- a/src/components/process-management/actions.ts
+++ b/src/components/process-management/actions.ts
@@ -109,7 +109,7 @@ function transformApiToFrontend(apiData: ApiProcess): Process {
     parentId: apiData.parent_id ? String(apiData.parent_id) : undefined,
     parentProcessCode: apiData.parent?.process_code ?? undefined,
     parentProcessName: apiData.parent?.process_name ?? undefined,
-    children: (apiData.children ?? []).map(transformProcessApiToFrontend),
+    children: (apiData.children ?? []).map(transformApiToFrontend),
     classificationRules: [...patternRules, ...individualRules],
     requiredWorkers: apiData.required_workers,
     equipmentInfo: apiData.equipment_info ?? undefined,
@@ -194,6 +194,7 @@ function transformFrontendToApi(data: ProcessFormData): Record<string, unknown>
   );
 
   return {
+    parent_id: data.parentId || null,
     process_name: data.processName,
     process_type: data.processType,
     department: data.department || null,
@@ -426,6 +427,23 @@ export async function getProcessOptions(): Promise<{
   };
 }
 
+/**
+ * 루트 공정 목록 조회 (부모 공정 선택 드롭다운용)
+ * parent_id가 null인 공정만 반환
+ */
+export async function getRootProcessOptions(): Promise<{
+  success: boolean;
+  data?: Array<{ id: string; processCode: string; processName: string }>;
+  error?: string;
+}> {
+  const result = await getProcessList({ size: 1000 });
+  if (!result.success || !result.data) return { success: false, error: result.error };
+  const roots = result.data.items
+    .filter(p => !p.parentId)
+    .map(p => ({ id: p.id, processCode: p.processCode, processName: p.processName }));
+  return { success: true, data: roots };
+}
+
 /**
  * 공정 통계
  */