diff --git a/posthog/cdp/site_functions.py b/posthog/cdp/site_functions.py
index f6ece18e28792..fa77c20a8f881 100644
--- a/posthog/cdp/site_functions.py
+++ b/posthog/cdp/site_functions.py
@@ -122,9 +122,13 @@ def get_transpiled_function(hog_function: HogFunction) -> str:
             callback(true);
         }
 
-        return {
-            processEvent: (globals) => processEvent(globals, posthog)
+        const response = {}
+
+        if (processEvent) {
+            response.processEvent = (globals) => processEvent(globals, posthog)
         }
+
+        return response
     }
 
     return { init: init };"""
diff --git a/posthog/cdp/test/test_site_functions.py b/posthog/cdp/test/test_site_functions.py
index 0b6c0bc1bb8a6..658b16ba41be0 100644
--- a/posthog/cdp/test/test_site_functions.py
+++ b/posthog/cdp/test/test_site_functions.py
@@ -98,9 +98,13 @@ def test_get_transpiled_function_basic(self):
             callback(true);
         }
 
-        return {
-            processEvent: (globals) => processEvent(globals, posthog)
+        const response = {}
+
+        if (processEvent) {
+            response.processEvent = (globals) => processEvent(globals, posthog)
         }
+
+        return response
     }
 
     return { init: init };
diff --git a/posthog/models/test/test_remote_config.py b/posthog/models/test/test_remote_config.py
index f83b6fef5ea86..d06ec45dcdc69 100644
--- a/posthog/models/test/test_remote_config.py
+++ b/posthog/models/test/test_remote_config.py
@@ -747,9 +747,13 @@ def test_renders_js_including_site_functions(self):
                     callback(true);
                 }
         
-                return {
-                    processEvent: (globals) => processEvent(globals, posthog)
+                const response = {}
+        
+                if (processEvent) {
+                    response.processEvent = (globals) => processEvent(globals, posthog)
                 }
+        
+                return response
             }
         
             return { init: init };
@@ -793,9 +797,13 @@ def test_renders_js_including_site_functions(self):
                     callback(true);
                 }
         
-                return {
-                    processEvent: (globals) => processEvent(globals, posthog)
+                const response = {}
+        
+                if (processEvent) {
+                    response.processEvent = (globals) => processEvent(globals, posthog)
                 }
+        
+                return response
             }
         
             return { init: init };