diff --git a/mrbgems/mruby-range-ext/src/range.c b/mrbgems/mruby-range-ext/src/range.c
index 633c97b73..9a88ef542 100644
--- a/mrbgems/mruby-range-ext/src/range.c
+++ b/mrbgems/mruby-range-ext/src/range.c
@@ -40,7 +40,7 @@ range_cover(mrb_state *mrb, mrb_value range)
   beg = RANGE_BEG(r);
   end = RANGE_END(r);
 
-  if (r_le(mrb, beg, val)) {
+  if (mrb_nil_p(beg) || r_le(mrb, beg, val)) {
     if (mrb_nil_p(end)) {
       return mrb_true_value();
     }