diff --git a/mrbgems/mruby-regexp/mrblib/regexp.rb b/mrbgems/mruby-regexp/mrblib/regexp.rb
index b50e221b3..84740d578 100644
--- a/mrbgems/mruby-regexp/mrblib/regexp.rb
+++ b/mrbgems/mruby-regexp/mrblib/regexp.rb
@@ -8,9 +8,7 @@ class Regexp
     @named_captures || {}
   end
 
-  def options
-    @flags.to_i
-  end
+  # options is implemented in C (internal flags -> Ruby constants conversion)
 
   def self.last_match(n = nil)
     md = $~
diff --git a/mrbgems/mruby-regexp/src/regexp.c b/mrbgems/mruby-regexp/src/regexp.c
index 77c0fe4dd..d580880f8 100644
--- a/mrbgems/mruby-regexp/src/regexp.c
+++ b/mrbgems/mruby-regexp/src/regexp.c
@@ -253,6 +253,34 @@ regexp_source(mrb_state *mrb, mrb_value self)
   return mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@source"));
 }
 
+/*
+ * Regexp#options - convert internal flags to Ruby constants
+ * Internal: IGNORECASE=1, MULTILINE=2, DOTALL=4, EXTENDED=8
+ * Ruby:     IGNORECASE=1, EXTENDED=2, MULTILINE=4
+ */
+static mrb_value
+regexp_options(mrb_state *mrb, mrb_value self)
+{
+  mrb_value flags_val = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@flags"));
+  uint32_t iflags = mrb_nil_p(flags_val) ? 0 : (uint32_t)mrb_integer(flags_val);
+  mrb_int opts = 0;
+  if (iflags & RE_FLAG_IGNORECASE) opts |= 1;  /* Regexp::IGNORECASE */
+  if (iflags & RE_FLAG_EXTENDED) opts |= 2;     /* Regexp::EXTENDED */
+  if (iflags & RE_FLAG_MULTILINE) opts |= 4;    /* Regexp::MULTILINE */
+  return mrb_fixnum_value(opts);
+}
+
+/*
+ * Regexp#casefold?
+ */
+static mrb_value
+regexp_casefold_p(mrb_state *mrb, mrb_value self)
+{
+  mrb_value flags_val = mrb_iv_get(mrb, self, mrb_intern_lit(mrb, "@flags"));
+  uint32_t iflags = mrb_nil_p(flags_val) ? 0 : (uint32_t)mrb_integer(flags_val);
+  return mrb_bool_value((iflags & RE_FLAG_IGNORECASE) != 0);
+}
+
 /*
  * Regexp#to_s - CRuby-compatible (?flags:source) format
  */
@@ -574,6 +602,8 @@ mrb_mruby_regexp_gem_init(mrb_state *mrb)
   mrb_define_method(mrb, re, "==", regexp_eql, MRB_ARGS_REQ(1));
   mrb_define_method(mrb, re, "eql?", regexp_eql, MRB_ARGS_REQ(1));
   mrb_define_method(mrb, re, "hash", regexp_hash, MRB_ARGS_NONE());
+  mrb_define_method(mrb, re, "options", regexp_options, MRB_ARGS_NONE());
+  mrb_define_method(mrb, re, "casefold?", regexp_casefold_p, MRB_ARGS_NONE());
 
   /* MatchData class */
   struct RClass *md = mrb_define_class(mrb, "MatchData", mrb->object_class);
diff --git a/mrbgems/mruby-regexp/test/regexp.rb b/mrbgems/mruby-regexp/test/regexp.rb
index 58abf2ff4..4cabb883d 100644
--- a/mrbgems/mruby-regexp/test/regexp.rb
+++ b/mrbgems/mruby-regexp/test/regexp.rb
@@ -149,6 +149,22 @@ assert("Regexp#hash") do
   assert_not_equal r1.hash, r3.hash
 end
 
+assert("Regexp#options") do
+  assert_equal 0, Regexp.new("abc").options
+  assert_equal Regexp::IGNORECASE, Regexp.new("abc", Regexp::IGNORECASE).options
+  assert_equal Regexp::MULTILINE, Regexp.new("abc", Regexp::MULTILINE).options
+  assert_equal Regexp::EXTENDED, Regexp.new("abc", Regexp::EXTENDED).options
+  assert_equal Regexp::IGNORECASE | Regexp::MULTILINE,
+               Regexp.new("abc", Regexp::IGNORECASE | Regexp::MULTILINE).options
+  assert_equal Regexp::IGNORECASE | Regexp::EXTENDED | Regexp::MULTILINE,
+               Regexp.new("abc", Regexp::IGNORECASE | Regexp::EXTENDED | Regexp::MULTILINE).options
+end
+
+assert("Regexp#casefold?") do
+  assert_true Regexp.new("abc", Regexp::IGNORECASE).casefold?
+  assert_false Regexp.new("abc").casefold?
+end
+
 assert("Regexp extended mode (x flag)") do
   # whitespace is ignored
   re = Regexp.new('a b c', Regexp::EXTENDED)