diff --git a/packages/kit/src/runtime/server/endpoint.js b/packages/kit/src/runtime/server/endpoint.js
index 94c232a47bca..0b8baa660535 100644
--- a/packages/kit/src/runtime/server/endpoint.js
+++ b/packages/kit/src/runtime/server/endpoint.js
@@ -63,7 +63,7 @@ export default async function render_route(request, route) {
 				(!type || type.startsWith('application/json'))
 			) {
 				headers = { ...headers, 'content-type': 'application/json; charset=utf-8' };
-				normalized_body = JSON.stringify(body || {});
+				normalized_body = JSON.stringify(typeof body === 'undefined' ? {} : body);
 			} else {
 				normalized_body = /** @type {import('types/hooks').StrictBody} */ (body);
 			}
diff --git a/packages/kit/test/apps/basics/src/routes/endpoint-output/_tests.js b/packages/kit/test/apps/basics/src/routes/endpoint-output/_tests.js
index a65e96fe43b8..781e73461fbe 100644
--- a/packages/kit/test/apps/basics/src/routes/endpoint-output/_tests.js
+++ b/packages/kit/test/apps/basics/src/routes/endpoint-output/_tests.js
@@ -36,4 +36,10 @@ export default function (test) {
 		const res = await fetch('/endpoint-output/empty');
 		assert.type(await res.buffer(), 'object');
 	});
+
+	test('null body returns null json value', null, async ({ fetch }) => {
+		const res = await fetch('/endpoint-output/null');
+		assert.equal(res.status, 200);
+		assert.equal(await res.json(), null);
+	});
 }
diff --git a/packages/kit/test/apps/basics/src/routes/endpoint-output/null.js b/packages/kit/test/apps/basics/src/routes/endpoint-output/null.js
new file mode 100644
index 000000000000..d6d2b9f71fae
--- /dev/null
+++ b/packages/kit/test/apps/basics/src/routes/endpoint-output/null.js
@@ -0,0 +1,4 @@
+/** @type {import('@sveltejs/kit').RequestHandler} */
+export function get() {
+	return { body: null };
+}