diff --git a/src/components/orders/OrderRegistration.tsx b/src/components/orders/OrderRegistration.tsx
index 3585dc6b..deea1be9 100644
--- a/src/components/orders/OrderRegistration.tsx
+++ b/src/components/orders/OrderRegistration.tsx
@@ -13,6 +13,7 @@
 
 import { useState, useEffect, useCallback } from "react";
 import { useDaumPostcode } from "@/hooks/useDaumPostcode";
+import { useClientList } from "@/hooks/useClientList";
 import { Input } from "@/components/ui/input";
 import { Textarea } from "@/components/ui/textarea";
 import { Button } from "@/components/ui/button";
@@ -134,15 +135,6 @@ const SHIPPING_COSTS = [
   { value: "negotiable", label: "협의" },
 ];
 
-// 샘플 발주처 데이터
-const SAMPLE_CLIENTS = [
-  { id: "C001", name: "태영건설(주)" },
-  { id: "C002", name: "현대건설(주)" },
-  { id: "C003", name: "GS건설(주)" },
-  { id: "C004", name: "대우건설(주)" },
-  { id: "C005", name: "포스코건설" },
-];
-
 interface OrderRegistrationProps {
   onBack: () => void;
   onSave: (formData: OrderFormData) => Promise<void>;
@@ -185,6 +177,14 @@ export function OrderRegistration({
   const [isSaving, setIsSaving] = useState(false);
   const [fieldErrors, setFieldErrors] = useState<FieldErrors>({});
 
+  // 거래처 목록 조회
+  const { clients, fetchClients, isLoading: isClientsLoading } = useClientList();
+
+  // 컴포넌트 마운트 시 거래처 목록 불러오기
+  useEffect(() => {
+    fetchClients({ onlyActive: true, size: 100 });
+  }, [fetchClients]);
+
   // Daum 우편번호 서비스
   const { openPostcode } = useDaumPostcode({
     onComplete: (result) => {
@@ -231,6 +231,7 @@ export function OrderRegistration({
     setForm((prev) => ({
       ...prev,
       selectedQuotation: quotation,
+      clientId: quotation.clientId || "",  // 견적의 발주처 ID 설정
       clientName: quotation.client,
       siteName: quotation.siteName,
       manager: quotation.manager || "",
@@ -238,6 +239,8 @@ export function OrderRegistration({
       items,
     }));
 
+    // 발주처 에러 초기화
+    clearFieldError("clientName");
     toast.success("견적 정보가 불러와졌습니다.");
   };
 
@@ -449,7 +452,7 @@ export function OrderRegistration({
               <Select
                 value={form.clientId}
                 onValueChange={(value) => {
-                  const client = SAMPLE_CLIENTS.find((c) => c.id === value);
+                  const client = clients.find((c) => c.id === value);
                   setForm((prev) => ({
                     ...prev,
                     clientId: value,
@@ -457,14 +460,15 @@ export function OrderRegistration({
                   }));
                   clearFieldError("clientName");
                 }}
+                disabled={!!form.selectedQuotation || isClientsLoading}
               >
                 <SelectTrigger className={cn(fieldErrors.clientName && "border-red-500")}>
-                  <SelectValue placeholder="발주처 선택">
-                    {form.clientName || "발주처 선택"}
+                  <SelectValue placeholder={isClientsLoading ? "불러오는 중..." : "발주처 선택"}>
+                    {form.clientName || (isClientsLoading ? "불러오는 중..." : "발주처 선택")}
                   </SelectValue>
                 </SelectTrigger>
                 <SelectContent>
-                  {SAMPLE_CLIENTS.map((client) => (
+                  {clients.map((client) => (
                     <SelectItem key={client.id} value={client.id}>
                       {client.name}
                     </SelectItem>