diff --git a/array.c b/array.c
index c2a4e85..485f617 100644
--- a/array.c
+++ b/array.c
@@ -3775,6 +3775,35 @@ rb_ary_shuffle(VALUE ary)
 }
 
 
+static VALUE
+ary_sample_with_replace(VALUE const ary, long const n)
+{
+    VALUE result;
+    VALUE* ptr_result;
+    long i;
+
+    VALUE const* const ptr = RARRAY_PTR(ary);
+    long const len = RARRAY_LEN(ary);
+
+    switch (n) {
+      case 0:
+        return rb_ary_new2(0);
+      case 1:
+        return rb_ary_new4(1, &ptr[(long)(rb_genrand_real()*len)]);
+      default:
+        break;
+    }
+    result = rb_ary_new2(n);
+    ptr_result = RARRAY_PTR(result);
+    RB_GC_GUARD(ary);
+    for (i = 0; i < n; ++i) {
+        long const j = (long)(rb_genrand_real()*len);
+        ptr_result[i] = ptr[j];
+    }
+    ARY_SET_LEN(result, n);
+    return result;
+}
+
 /*
  *  call-seq:
  *     ary.sample        -> obj
@@ -3792,7 +3821,7 @@ rb_ary_shuffle(VALUE ary)
 static VALUE
 rb_ary_sample(int argc, VALUE *argv, VALUE ary)
 {
-    VALUE nv, result, *ptr;
+    VALUE nv, replace, result, *ptr;
     long n, len, i, j, k, idx[10];
 
     len = RARRAY_LEN(ary);
@@ -3801,9 +3830,12 @@ rb_ary_sample(int argc, VALUE *argv, VALUE ary)
 	i = len == 1 ? 0 : (long)(rb_genrand_real()*len);
 	return RARRAY_PTR(ary)[i];
     }
-    rb_scan_args(argc, argv, "1", &nv);
+    rb_scan_args(argc, argv, "12", &nv, &replace);
     n = NUM2LONG(nv);
     if (n < 0) rb_raise(rb_eArgError, "negative sample number");
+    if (RTEST(replace)) {
+      return ary_sample_with_replace(ary, n);
+    }
     ptr = RARRAY_PTR(ary);
     len = RARRAY_LEN(ary);
     if (n > len) n = len;
diff --git a/test/ruby/test_array.rb b/test/ruby/test_array.rb
index e8edcc2..837ce7b 100644
--- a/test/ruby/test_array.rb
+++ b/test/ruby/test_array.rb
@@ -1894,7 +1894,7 @@ class TestArray < Test::Unit::TestCase
     (0..20).each do |n|
       100.times do
         b = a.sample(n)
-        assert_equal([n, 18].min, b.uniq.size)
+        assert_equal([n, 18].min, b.size)
         assert_equal(a, (a | b).sort)
         assert_equal(b.sort, (a & b).sort)
       end
@@ -1909,6 +1909,62 @@ class TestArray < Test::Unit::TestCase
     assert_raise(ArgumentError, '[ruby-core:23374]') {[1, 2].sample(-1)}
   end
 
+  def test_sample_without_replace
+    100.times do
+      samples = [2, 1, 0].sample(2, false)
+      samples.each{|sample|
+        assert([0, 1, 2].include?(sample))
+      }
+    end
+
+    srand(0)
+    a = (1..18).to_a
+    (0..20).each do |n|
+      100.times do
+        b = a.sample(n, false)
+        assert_equal([n, 18].min, b.size)
+        assert_equal(a, (a | b).sort)
+        assert_equal(b.sort, (a & b).sort)
+      end
+
+      h = Hash.new(0)
+      1000.times do
+        a.sample(n, false).each {|x| h[x] += 1 }
+      end
+      assert_operator(h.values.min * 2, :>=, h.values.max) if n != 0
+    end
+
+    assert_raise(ArgumentError, '[ruby-core:23374]') {[1, 2].sample(-1, false)}
+  end
+
+  def test_sample_with_replace
+    100.times do
+      samples = [2, 1, 0].sample(2, true)
+      samples.each{|sample|
+        assert([0, 1, 2].include?(sample))
+      }
+    end
+
+    srand(0)
+    a = (1..18).to_a
+    (0..20).each do |n|
+      100.times do
+        b = a.sample(n, true)
+        assert_equal(n, b.size)
+        assert_equal(a, (a | b).sort)
+        assert_equal(b.sort.uniq, (a & b).sort)
+      end
+
+      h = Hash.new(0)
+      1000.times do
+        a.sample(n, true).each {|x| h[x] += 1 }
+      end
+      assert_operator(h.values.min * 2, :>=, h.values.max) if n != 0
+    end
+
+    assert_raise(ArgumentError, '[ruby-core:23374]') {[1, 2].sample(-1, true)}
+  end
+
   def test_cycle
     a = []
     [0, 1, 2].cycle do |i|