diff --git a/src/components/process-management/actions.ts b/src/components/process-management/actions.ts
index 5dbf2971..2f780b83 100644
--- a/src/components/process-management/actions.ts
+++ b/src/components/process-management/actions.ts
@@ -13,6 +13,9 @@ import type { Process, ProcessFormData, ClassificationRule, IndividualItem, Proc
 interface ApiProcess {
   id: number;
   tenant_id: number;
+  parent_id: number | null;
+  parent?: { id: number; process_code: string; process_name: string } | null;
+  children?: ApiProcess[];
   process_code: string;
   process_name: string;
   description: string | null;
@@ -103,7 +106,10 @@ function transformApiToFrontend(apiData: ApiProcess): Process {
     workLogTemplateName: apiData.work_log_template_relation?.name ?? undefined,
     needsInspection: apiData.options?.needs_inspection ?? false,
     needsWorkLog: apiData.options?.needs_work_log ?? false,
-    processGroup: apiData.options?.process_group ?? undefined,
+    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),
     classificationRules: [...patternRules, ...individualRules],
     requiredWorkers: apiData.required_workers,
     equipmentInfo: apiData.equipment_info ?? undefined,
diff --git a/src/components/production/WorkerScreen/index.tsx b/src/components/production/WorkerScreen/index.tsx
index f1e311e5..89d69681 100644
--- a/src/components/production/WorkerScreen/index.tsx
+++ b/src/components/production/WorkerScreen/index.tsx
@@ -289,18 +289,26 @@ export default function WorkerScreen() {
     return processListCache.filter((p) => p.status === '사용중');
   }, [processListCache]);
 
-  // 그룹별 탭 구성 (process_group 기준, 없으면 공정명 사용)
+  // 그룹별 탭 구성 (parent_id 기반 트리 구조)
   const groupedTabs = useMemo(() => {
     const groupMap = new Map<string, Process[]>();
+
+    // 루트 공정 기준 그룹 구성
     activeProcesses.forEach((p) => {
-      const group = p.processGroup || p.processName;
+      if (p.parentId) return; // 자식은 건너뜀
+
+      const group = p.processName;
       if (!groupMap.has(group)) groupMap.set(group, []);
       groupMap.get(group)!.push(p);
+
+      // 자식 공정 추가
+      const children = activeProcesses.filter((c) => c.parentId === p.id);
+      children.forEach((c) => groupMap.get(group)!.push(c));
     });
+
     return Array.from(groupMap.entries()).map(([group, processes]) => ({
       group,
       processes,
-      // 그룹 내 첫 번째 공정 ID를 탭 value로 사용
       defaultProcessId: processes[0].id,
     }));
   }, [activeProcesses]);
@@ -315,8 +323,9 @@ export default function WorkerScreen() {
   const activeGroup = useMemo(() => {
     const process = processListCache.find((p) => p.id === activeTab);
     if (!process) return null;
-    const group = process.processGroup || process.processName;
-    return groupedTabs.find((g) => g.group === group) || null;
+    // 자식이면 부모 공정명, 루트면 자기 공정명
+    const groupName = process.parentProcessName || process.processName;
+    return groupedTabs.find((g) => g.group === groupName) || null;
   }, [activeTab, processListCache, groupedTabs]);
 
   // 공정 목록 로드 후 첫 번째 그룹을 기본 선택
diff --git a/src/types/process.ts b/src/types/process.ts
index 1cd825e8..16b90b0b 100644
--- a/src/types/process.ts
+++ b/src/types/process.ts
@@ -92,8 +92,11 @@ export interface Process {
   // 단계 목록
   steps?: ProcessStep[];
 
-  // 공정 그룹 (같은 그룹은 하나의 탭으로 표시)
-  processGroup?: string;
+  // 부모-자식 트리 구조
+  parentId?: string;
+  parentProcessCode?: string;
+  parentProcessName?: string;
+  children?: Process[];
 
   // 상태
   status: ProcessStatus;
@@ -105,6 +108,7 @@ export interface Process {
 
 // 공정 등록/수정 폼 데이터
 export interface ProcessFormData {
+  parentId?: number;
   processName: string;
   processType: ProcessType;
   department: string;