diff --git a/WebContent/jsp/onl/transaction/apim/apiInterfaceManDetail.jsp b/WebContent/jsp/onl/transaction/apim/apiInterfaceManDetail.jsp
index 8da7778..2c3e6f3 100644
--- a/WebContent/jsp/onl/transaction/apim/apiInterfaceManDetail.jsp
+++ b/WebContent/jsp/onl/transaction/apim/apiInterfaceManDetail.jsp
@@ -1608,8 +1608,10 @@
             <button type="button" class="cssbtn" id="btn_json_export" level="R" status="DETAIL,NEW"><i class="material-icons">download</i> <%=localeMessage.getString("button.exportJson")%></button></button>
             <button type="button" class="cssbtn" id="btn_delete" level="W" status="DETAIL"><i class="material-icons">delete</i> <%= localeMessage.getString("button.delete") %></button>
             <button type="button" class="cssbtn" id="btn_modify" level="R" status="DETAIL,NEW"><i class="material-icons">save</i> <%= localeMessage.getString("button.modify") %></button>
-            <!-- v1: 기존 API 스펙 (모달) — 기능 비교용 복원 -->
-            <button type="button" class="cssbtn" id="btn_api_spec" level="R" status="DETAIL"><i class="material-icons">description</i> API 스펙(삭제예정)</button>
+            <%-- v1: 기존 API 스펙 (모달). PTL_PROPERTY(Portal / djb.apispec.v1.enabled) 로 노출 제어. --%>
+            <c:if test="${apiSpecV1Enabled}">
+            <button type="button" class="cssbtn" id="btn_api_spec" level="R" status="DETAIL"><i class="material-icons">description</i> API 스펙</button>
+            </c:if>
             <!-- v2: 신규 OpenAPI Spec (새 탭) -->
             <button type="button" class="cssbtn" id="btn_openapi_spec" level="R" status="DETAIL"><i class="material-icons">api</i> OpenAPI Spec</button>
             <button type="button" class="cssbtn" id="btn_previous" level="R" status="DETAIL,NEW"><i class="material-icons">arrow_back</i> <%= localeMessage.getString("button.previous") %></button>
diff --git a/src/main/java/com/eactive/eai/rms/onl/transaction/apim/ApiInterfaceController.java b/src/main/java/com/eactive/eai/rms/onl/transaction/apim/ApiInterfaceController.java
index 0f21a97..763fe2f 100644
--- a/src/main/java/com/eactive/eai/rms/onl/transaction/apim/ApiInterfaceController.java
+++ b/src/main/java/com/eactive/eai/rms/onl/transaction/apim/ApiInterfaceController.java
@@ -1,5 +1,6 @@
 package com.eactive.eai.rms.onl.transaction.apim;
 
+import com.eactive.apim.portal.portalproperty.service.PortalPropertyService;
 import com.eactive.eai.agent.command.Command;
 import com.eactive.eai.agent.command.CommonCommand;
 import com.eactive.eai.rms.common.base.OnlBaseAnnotationController;
@@ -24,6 +25,7 @@ import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestParam;
@@ -41,13 +43,19 @@ public class ApiInterfaceController extends OnlBaseAnnotationController {
 
 	public static final Log logger = LogFactory.getLog(ApiInterfaceController.class);
 
+	// v1 "API 스펙"(모달) 버튼 노출 여부. PTL_PROPERTY 그룹 'Portal'. 미설정 시 true(현행 노출 유지)로 생성.
+	private static final String API_SPEC_V1_ENABLED_KEY = "djb.apispec.v1.enabled";
+
 	private final ApiInterfaceService service;
 	private final ClientEntityService clientEntityService;
+	private final PortalPropertyService portalPropertyService;
 
 	@Autowired
-	public ApiInterfaceController(ApiInterfaceService service, ClientEntityService clientEntityService) {
+	public ApiInterfaceController(ApiInterfaceService service, ClientEntityService clientEntityService,
+			PortalPropertyService portalPropertyService) {
 		this.service = service;
 		this.clientEntityService = clientEntityService;
+		this.portalPropertyService = portalPropertyService;
 	}
 
 	@GetMapping(value = "/onl/transaction/apim/apiInterfaceMan.view")
@@ -55,10 +63,25 @@ public class ApiInterfaceController extends OnlBaseAnnotationController {
 	}
 
 	@GetMapping(value = "/onl/transaction/apim/apiInterfaceMan.view", params = "cmd=DETAIL")
-	public String viewDetail() {
+	public String viewDetail(Model model) {
+		model.addAttribute("apiSpecV1Enabled", resolveApiSpecV1Enabled());
 		return "/onl/transaction/apim/apiInterfaceManDetail";
 	}
 
+	/** v1 API 스펙 버튼 노출 여부 조회(레거시 Y/N 값도 허용). 미설정/파싱불가 시 true. */
+	private boolean resolveApiSpecV1Enabled() {
+		String v = portalPropertyService.getOrCreateProperty("Portal", API_SPEC_V1_ENABLED_KEY, "true",
+				"API 인터페이스 상세의 v1 'API 스펙'(모달) 버튼 노출 여부(true/false)");
+		if (v == null) {
+			return true;
+		}
+		String s = v.trim();
+		if (s.equalsIgnoreCase("false") || s.equalsIgnoreCase("N")) {
+			return false;
+		}
+		return true;
+	}
+
 	@PostMapping(value= "/onl/transaction/apim/apiInterfaceMan.json", params = "cmd=LIST")
 	public ResponseEntity<GridResponse<ApiInterfaceUI>> selectList(EAIMessageUISearch eaiMessageUISearch,
 			@RequestParam(value = "sortName", required = false, defaultValue = "lastModifiedDate") String sortname,