diff --git a/test/ruby/test_marshal.rb b/test/ruby/test_marshal.rb
index 79d9577737..69e92488f2 100644
--- a/test/ruby/test_marshal.rb
+++ b/test/ruby/test_marshal.rb
@@ -570,13 +570,13 @@ class TestMarshal < Test::Unit::TestCase
   def test_class_ivar
     assert_raise(TypeError) {Marshal.load("\x04\x08Ic\x1bTestMarshal::TestClass\x06:\x0e@ivar_bug\"\x08bug")}
     assert_raise(TypeError) {Marshal.load("\x04\x08IM\x1bTestMarshal::TestClass\x06:\x0e@ivar_bug\"\x08bug")}
-    assert_not_operator(TestClass, :instance_variable_defined?, :@bug)
+    assert_not_operator(TestClass, :instance_variable_defined?, :@ivar_bug)
   end
 
   def test_module_ivar
     assert_raise(TypeError) {Marshal.load("\x04\x08Im\x1cTestMarshal::TestModule\x06:\x0e@ivar_bug\"\x08bug")}
     assert_raise(TypeError) {Marshal.load("\x04\x08IM\x1cTestMarshal::TestModule\x06:\x0e@ivar_bug\"\x08bug")}
-    assert_not_operator(TestModule, :instance_variable_defined?, :@bug)
+    assert_not_operator(TestModule, :instance_variable_defined?, :@ivar_bug)
   end
 
   class TestForRespondToFalse