diff --git a/src/functions_framework/__init__.py b/src/functions_framework/__init__.py
index 74329dba..58c7b6c1 100644
--- a/src/functions_framework/__init__.py
+++ b/src/functions_framework/__init__.py
@@ -256,9 +256,15 @@ def handle_none(rv):
 
     # Extract the target function from the source file
     if not hasattr(source_module, target):
+        non_target_functions = ", ".join(
+            "'{attr}'".format(attr=attr)
+            for attr in dir(source_module)
+            if isinstance(getattr(source_module, attr), types.FunctionType)
+        )
+
         raise MissingTargetException(
-            "File {source} is expected to contain a function named {target}".format(
-                source=source, target=target
+            "File {source} is expected to contain a function named '{target}' (found: {non_target_functions} instead)".format(
+                source=source, target=target, non_target_functions=non_target_functions
             )
         )
     function = getattr(source_module, target)
diff --git a/tests/test_functions.py b/tests/test_functions.py
index 176e2bb1..2969f5c8 100644
--- a/tests/test_functions.py
+++ b/tests/test_functions.py
@@ -277,7 +277,8 @@ def test_invalid_function_definition_multiple_entry_points():
         create_app(target, source, "event")
 
     assert re.match(
-        "File .* is expected to contain a function named function", str(excinfo.value)
+        "File .* is expected to contain a function named 'function' \(found: 'fun', 'myFunctionBar', 'myFunctionFoo' instead\)",
+        str(excinfo.value),
     )
 
 
@@ -289,7 +290,7 @@ def test_invalid_function_definition_multiple_entry_points_invalid_function():
         create_app(target, source, "event")
 
     assert re.match(
-        "File .* is expected to contain a function named invalidFunction",
+        "File .* is expected to contain a function named 'invalidFunction' \(found: 'fun', 'myFunctionBar', 'myFunctionFoo' instead\)",
         str(excinfo.value),
     )