diff --git a/.hongdown.toml b/.hongdown.toml
index fa850b8b0..a2acc0c0c 100644
--- a/.hongdown.toml
+++ b/.hongdown.toml
@@ -7,6 +7,7 @@ exclude = [
   ".github/copilot-instructions.md",
   "AGENT.md",
   "CLAUDE.md",
+  "changes.d/**",
   "GEMINI.md",
   "WARP.md",
   "packages/fedify/src/cfworkers/**",
diff --git a/CHANGES.md b/CHANGES.md
index 8964d5f04..ef4be9245 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -8,6 +8,16 @@ Version 2.0.25
 
 To be released.
 
+### @fedify/elysia
+
+ -  Fixed duplicate response headers on Elysia 1.4.18 and earlier, which
+    append both `set.headers` and the returned `Response`'s own headers
+    without deduplication.  The `fedify()` plugin no longer sets the headers
+    in both places.  [[#970], [#972] by Kyujin Lim\]
+
+[#970]: https://github.com/fedify-dev/fedify/issues/970
+[#972]: https://github.com/fedify-dev/fedify/pull/972
+
 
 Version 2.0.24
 --------------
diff --git a/changes.d/elysia/duplicate-response-headers.md b/changes.d/elysia/duplicate-response-headers.md
new file mode 100644
index 000000000..a913ba37e
--- /dev/null
+++ b/changes.d/elysia/duplicate-response-headers.md
@@ -0,0 +1,9 @@
+---
+links:
+  '#970': https://github.com/fedify-dev/fedify/issues/970
+  '#972': https://github.com/fedify-dev/fedify/pull/972
+---
+ -  Fixed duplicate response headers on Elysia 1.4.18 and earlier, which
+    append both `set.headers` and the returned `Response`'s own headers
+    without deduplication.  The `fedify()` plugin no longer sets the headers
+    in both places.  [[#970], [#972] by Kyujin Lim]
diff --git a/packages/elysia/src/index.ts b/packages/elysia/src/index.ts
index 8a1648abb..9381d0d13 100644
--- a/packages/elysia/src/index.ts
+++ b/packages/elysia/src/index.ts
@@ -42,15 +42,15 @@ export const fedify = <TContextData = unknown>(
         if (!notFound && !notAcceptable) {
           set.status = response.status;
 
-          response.headers.forEach((value, key) => {
-            set.headers[key] = value;
-          });
-
           // Return response body if it exists
           if (response.body) {
             return response;
           }
 
+          response.headers.forEach((value, key) => {
+            set.headers[key] = value;
+          });
+
           // Return empty response for successful requests without body
           return new Response(null, { status: response.status });
         }