diff --git a/CHANGELOG.md b/CHANGELOG.md
index 494e36427afb..6a6bafc368ba 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 ### Fixes
 
 - `[jest-mock]` Treat cjs modules as objects so they can be mocked ([#13513](https://github.com/facebook/jest/pull/13513))
+- `[jest-worker]` Ignore IPC messages not intended for Jest ([#13543](https://github.com/facebook/jest/pull/13543))
 
 ### Chore & Maintenance
 
diff --git a/packages/jest-worker/src/workers/ChildProcessWorker.ts b/packages/jest-worker/src/workers/ChildProcessWorker.ts
index e3999fa49e1a..f9652edd2b2d 100644
--- a/packages/jest-worker/src/workers/ChildProcessWorker.ts
+++ b/packages/jest-worker/src/workers/ChildProcessWorker.ts
@@ -255,6 +255,9 @@ export default class ChildProcessWorker
   }
 
   private _onMessage(response: ParentMessage) {
+    // Ignore messages not intended for us
+    if (!Array.isArray(response)) return;
+
     // TODO: Add appropriate type check
     let error: any;
 
@@ -311,7 +314,8 @@ export default class ChildProcessWorker
         break;
 
       default:
-        throw new TypeError(`Unexpected response from worker: ${response[0]}`);
+        // Ignore messages not intended for us
+        break;
     }
   }