diff --git a/mrbgems/mruby-exit/src/mruby-exit.c b/mrbgems/mruby-exit/src/mruby-exit.c
index f16b2cb71..046695c11 100644
--- a/mrbgems/mruby-exit/src/mruby-exit.c
+++ b/mrbgems/mruby-exit/src/mruby-exit.c
@@ -10,7 +10,7 @@
 #endif
 
 static mrb_value
-f_exit(mrb_state *mrb, mrb_value self)
+f_exit_bang(mrb_state *mrb, mrb_value self)
 {
   mrb_value status = mrb_true_value();
   int istatus;
@@ -28,7 +28,8 @@ f_exit(mrb_state *mrb, mrb_value self)
 void
 mrb_mruby_exit_gem_init(mrb_state* mrb)
 {
-  mrb_define_method(mrb, mrb->kernel_module, "exit", f_exit, MRB_ARGS_OPT(1));
+  mrb_define_method(mrb, mrb->kernel_module, "exit", f_exit_bang, MRB_ARGS_OPT(1));
+  mrb_define_method(mrb, mrb->kernel_module, "exit!", f_exit_bang, MRB_ARGS_OPT(1));
 }
 
 void