diff --git a/experimental/packages/opentelemetry-instrumentation-fetch/test/fetch.test.ts b/experimental/packages/opentelemetry-instrumentation-fetch/test/fetch.test.ts
index e76d9843248..955c734fadd 100644
--- a/experimental/packages/opentelemetry-instrumentation-fetch/test/fetch.test.ts
+++ b/experimental/packages/opentelemetry-instrumentation-fetch/test/fetch.test.ts
@@ -1212,5 +1212,18 @@ describe('fetch', () => {
       const events = span.events;
       assert.strictEqual(events.length, 0, 'number of events is wrong');
     });
+
+    it('should still add the CONTENT_LENGTH attribute', () => {
+      const span: tracing.ReadableSpan = exportSpy.args[1][0][0];
+      const attributes = span.attributes;
+      const responseContentLength = attributes[
+        SEMATTRS_HTTP_RESPONSE_CONTENT_LENGTH
+      ] as number;
+      assert.strictEqual(
+        responseContentLength,
+        30,
+        `attributes ${SEMATTRS_HTTP_RESPONSE_CONTENT_LENGTH} is <= 0`
+      );
+    });
   });
 });