diff --git a/include/mruby.h b/include/mruby.h
index 7dc1e697d..8a0396753 100644
--- a/include/mruby.h
+++ b/include/mruby.h
@@ -312,7 +312,7 @@ typedef struct mrb_state {
   struct RClass *eException_class;
   struct RClass *eStandardError_class;
   struct RObject *nomem_err;              /* pre-allocated NoMemoryError */
-  struct RObject *stack_err;              /* pre-allocated SysStackError */
+  struct RObject *stack_err;              /* pre-allocated SystemStackError */
 #ifdef MRB_GC_FIXED_ARENA
   struct RObject *arena_err;              /* pre-allocated arena overflow error */
 #endif