diff --git a/WebContent/jsp/onl/apim/approval/portalAppApprovalManPopup.jsp b/WebContent/jsp/onl/apim/approval/portalAppApprovalManPopup.jsp
index 1803542..bc6c93b 100644
--- a/WebContent/jsp/onl/apim/approval/portalAppApprovalManPopup.jsp
+++ b/WebContent/jsp/onl/apim/approval/portalAppApprovalManPopup.jsp
@@ -264,6 +264,16 @@
 
                     $("#clientName").text(data.clientName);
 
+                    // 신청 사유. 해지 신청은 사유 입력이 필수이므로 "해지 사유"로 표기하고, 그 외 유형은 "신청 사유"
+                    if (data.requestReason) {
+                        $("#requestReasonLabel").text(data.requestType === 'DELETE' ? "해지 사유" : "신청 사유");
+                        $("#requestReason").text(data.requestReason);
+                        $("#requestReasonRow").show();
+                    } else {
+                        $("#requestReason").text("");
+                        $("#requestReasonRow").hide();
+                    }
+
                     var apiServiceHtml = "";
                     for (var i = 0; i < data.apiServices.length; i++) {
                         var apiService = data.apiServices[i];
@@ -365,6 +375,10 @@
                 <th style="width:20%;">이름</th>
                 <td><span id="clientName"></span></td>
             </tr>
+            <tr id="requestReasonRow" style="display:none;">
+                <th style="width:20%;"><span id="requestReasonLabel">신청 사유</span></th>
+                <td><span id="requestReason" style="white-space: pre-wrap;"></span></td>
+            </tr>
         </table>
         <div class="title">API 목록</div>
         <table id="apisTable" class="table_row" cellspacing="0">
diff --git a/src/main/java/com/eactive/eai/rms/onl/apim/approval/PortalApprovalManService.java b/src/main/java/com/eactive/eai/rms/onl/apim/approval/PortalApprovalManService.java
index c005c90..e74f828 100644
--- a/src/main/java/com/eactive/eai/rms/onl/apim/approval/PortalApprovalManService.java
+++ b/src/main/java/com/eactive/eai/rms/onl/apim/approval/PortalApprovalManService.java
@@ -244,6 +244,8 @@ public class PortalApprovalManService extends BaseService {
 
                 appApprovalUI.setApprovalDetail(appRequest.getReason());
                 appApprovalUI.setClientName(appRequest.getClientName());
+                // 신청 사유는 상세 내용과 별개 항목으로도 내려준다(해지 신청 화면에서 "해지 사유"로 표기)
+                appApprovalUI.setRequestReason(appRequest.getReason());
 
                 appApprovalUI.getApprovers().forEach(approver -> {
                     if (approver.getUser() == null) {
diff --git a/src/main/java/com/eactive/eai/rms/onl/apim/approval/app/PortalAppApprovalUI.java b/src/main/java/com/eactive/eai/rms/onl/apim/approval/app/PortalAppApprovalUI.java
index 4cf9ae9..b291ac2 100644
--- a/src/main/java/com/eactive/eai/rms/onl/apim/approval/app/PortalAppApprovalUI.java
+++ b/src/main/java/com/eactive/eai/rms/onl/apim/approval/app/PortalAppApprovalUI.java
@@ -30,4 +30,7 @@ public class PortalAppApprovalUI extends PortalApprovalUI {
 
     //DELETE 승인 시 선택된 GW 처리방식 (승인 완료 건 상세 표시용)
     private GwAction gwAction;
+
+    //신청자가 입력한 사유(PTL_APP_REQUEST.REASON). 해지 신청은 사유가 필수라 별도 항목으로 노출한다.
+    private String requestReason;
 }