diff --git a/devfront/src/features/clients/ClientDetailsPage.tsx b/devfront/src/features/clients/ClientDetailsPage.tsx
index 82e43d43..7a502957 100644
--- a/devfront/src/features/clients/ClientDetailsPage.tsx
+++ b/devfront/src/features/clients/ClientDetailsPage.tsx
@@ -213,11 +213,15 @@ function ClientDetailsPage() {
     },
   ];
 
-  // Client Secret from API
+  const hasClientSecret = client.type === "private";
   const secretPlaceholder = "SECRET_NOT_AVAILABLE";
-  const clientSecret = client?.clientSecret || secretPlaceholder;
+  const clientSecret = hasClientSecret
+    ? client?.clientSecret || secretPlaceholder
+    : t("ui.common.na", "N/A");
   const displaySecret =
-    clientSecret === secretPlaceholder
+    !hasClientSecret
+      ? t("msg.dev.clients.details.secret_not_applicable", "PKCE 앱에는 Client Secret이 없습니다.")
+      : clientSecret === secretPlaceholder
       ? t("msg.dev.clients.details.secret_unavailable", "SECRET_NOT_AVAILABLE")
       : clientSecret;
 
@@ -327,61 +331,73 @@ function ClientDetailsPage() {
                       {showSecret ? displaySecret : "••••••••••••••••"}
                     </p>
                     <div className="flex gap-2 shrink-0">
-                      <Button
-                        variant="secondary"
-                        size="icon"
-                        onClick={() => setShowSecret(!showSecret)}
-                        aria-label={
-                          showSecret
-                            ? t(
-                                "ui.dev.clients.details.secret.hide",
-                                "비밀키 숨기기",
+                      {hasClientSecret ? (
+                        <>
+                          <Button
+                            variant="secondary"
+                            size="icon"
+                            onClick={() => setShowSecret(!showSecret)}
+                            aria-label={
+                              showSecret
+                                ? t(
+                                    "ui.dev.clients.details.secret.hide",
+                                    "비밀키 숨기기",
+                                  )
+                                : t(
+                                    "ui.dev.clients.details.secret.show",
+                                    "비밀키 보기",
+                                  )
+                            }
+                          >
+                            {showSecret ? (
+                              <EyeOff className="h-4 w-4" />
+                            ) : (
+                              <Eye className="h-4 w-4" />
+                            )}
+                          </Button>
+                          <Button
+                            variant="secondary"
+                            size="icon"
+                            onClick={handleRotateSecret}
+                            disabled={rotateMutation.isPending}
+                            title={t(
+                              "ui.dev.clients.details.secret.rotate",
+                              "비밀키 재발급 (Rotate)",
+                            )}
+                          >
+                            <RefreshCw
+                              className={cn(
+                                "h-4 w-4",
+                                rotateMutation.isPending && "animate-spin",
+                              )}
+                            />
+                          </Button>
+                          <CopyButton
+                            value={clientSecret}
+                            disabled={
+                              !showSecret && clientSecret === secretPlaceholder
+                            }
+                            onCopy={() =>
+                              toast(
+                                t(
+                                  "msg.dev.clients.details.copy_client_secret",
+                                  "Client Secret이 복사되었습니다.",
+                                ),
                               )
-                            : t(
-                                "ui.dev.clients.details.secret.show",
-                                "비밀키 보기",
-                              )
-                        }
-                      >
-                        {showSecret ? (
-                          <EyeOff className="h-4 w-4" />
-                        ) : (
-                          <Eye className="h-4 w-4" />
-                        )}
-                      </Button>
-                      <Button
-                        variant="secondary"
-                        size="icon"
-                        onClick={handleRotateSecret}
-                        disabled={rotateMutation.isPending}
-                        title={t(
-                          "ui.dev.clients.details.secret.rotate",
-                          "비밀키 재발급 (Rotate)",
-                        )}
-                      >
-                        <RefreshCw
-                          className={cn(
-                            "h-4 w-4",
-                            rotateMutation.isPending && "animate-spin",
-                          )}
-                        />
-                      </Button>
-                      <CopyButton
-                        value={clientSecret}
-                        disabled={
-                          !showSecret && clientSecret === secretPlaceholder
-                        }
-                        onCopy={() =>
-                          toast(
-                            t(
-                              "msg.dev.clients.details.copy_client_secret",
-                              "Client Secret이 복사되었습니다.",
-                            ),
-                          )
-                        }
-                      />
+                            }
+                          />
+                        </>
+                      ) : null}
                     </div>
                   </div>
+                  {!hasClientSecret ? (
+                    <p className="mt-2 text-sm text-muted-foreground">
+                      {t(
+                        "msg.dev.clients.details.secret_not_applicable",
+                        "PKCE 앱에는 Client Secret이 없습니다.",
+                      )}
+                    </p>
+                  ) : null}
                 </div>
               </CardContent>
             </Card>
diff --git a/devfront/src/locales/en.toml b/devfront/src/locales/en.toml
index 17077a4a..edfdf75a 100644
--- a/devfront/src/locales/en.toml
+++ b/devfront/src/locales/en.toml
@@ -362,6 +362,7 @@ create_forbidden = "You do not have permission to create this RP. Ask an adminis
 save_error = "Save Error"
 save_forbidden = "You do not have permission to edit this RP. Ask an administrator to grant RP General Settings or RP Admin relationship."
 secret_rotated = "Secret Rotated"
+secret_not_applicable = "PKCE apps do not have a client secret."
 secret_unavailable = "SECRET_NOT_AVAILABLE"
 subtitle = "Manage OIDC credentials and endpoints."
 
diff --git a/devfront/src/locales/ko.toml b/devfront/src/locales/ko.toml
index b46e0428..fa373fed 100644
--- a/devfront/src/locales/ko.toml
+++ b/devfront/src/locales/ko.toml
@@ -362,6 +362,7 @@ create_forbidden = "이 RP를 생성할 권한이 없습니다.\n관리자에게
 save_error = "저장 실패: {{error}}"
 save_forbidden = "이 RP 설정을 수정할 권한이 없습니다.\n관리자에게 RP 일반 설정 또는 RP 관리자 관계 부여를 요청해 주세요."
 secret_rotated = "Client Secret이 재발급되었습니다."
+secret_not_applicable = "PKCE 앱에는 Client Secret이 없습니다."
 secret_unavailable = "SECRET_NOT_AVAILABLE"
 subtitle = "OIDC 자격 증명과 엔드포인트를 관리합니다."
 
diff --git a/devfront/src/locales/template.toml b/devfront/src/locales/template.toml
index 91f3e09d..c8eaae93 100644
--- a/devfront/src/locales/template.toml
+++ b/devfront/src/locales/template.toml
@@ -408,6 +408,7 @@ create_forbidden = ""
 save_error = ""
 save_forbidden = ""
 secret_rotated = ""
+secret_not_applicable = ""
 secret_unavailable = ""
 subtitle = ""