diff --git a/ext/opencv/cvmat.cpp b/ext/opencv/cvmat.cpp
index c1d01d5..9735b9a 100644
--- a/ext/opencv/cvmat.cpp
+++ b/ext/opencv/cvmat.cpp
@@ -2393,8 +2393,8 @@ rb_abs_diff(VALUE self, VALUE val)
 VALUE
 rb_normalize(int argc, VALUE *argv, VALUE self)
 {
-  VALUE alphaVal, betaVal, normTypeVal;
-  rb_scan_args(argc, argv, "03", &alphaVal, &betaVal, &normTypeVal);
+  VALUE alphaVal, betaVal, normTypeVal, maskVal;
+  rb_scan_args(argc, argv, "04", &alphaVal, &betaVal, &normTypeVal, &maskVal);
   
   const double alpha = alphaVal != Qnil ? NUM2DBL(alphaVal) : 1.0;
   const double beta = betaVal != Qnil ? NUM2DBL(betaVal) : 0.0;
@@ -2405,11 +2405,18 @@ rb_normalize(int argc, VALUE *argv, VALUE self)
     const cv::Mat selfMat(CVMAT(self));
     cv::Mat destMat(CVMAT(dest));
     
-    cv::normalize(selfMat, destMat, alpha, beta, normType);
+    if (NIL_P(maskVal)) {
+      cv::normalize(selfMat, destMat, alpha, beta, normType);
+    }
+    else {
+      cv::Mat maskMat(MASK(maskVal));
+      cv::normalize(selfMat, destMat, alpha, beta, normType, -1, maskMat);
+    }
     
   } catch (cv::Exception& e) {
     raise_cverror(e);
   }
+
   return dest;
 }
 
diff --git a/test/test_cvmat.rb b/test/test_cvmat.rb
index fe8dae7..f6aa9d8 100755
--- a/test/test_cvmat.rb
+++ b/test/test_cvmat.rb
@@ -2023,6 +2023,15 @@ class TestCvMat < OpenCVTestCase
       assert_in_delta(x, mminmax[i][0], 0.001)
     }
 
+    mask = mat.to_8u.zero
+    mask[0, 0] = CvScalar.new(255, 0, 0)
+    mask[1, 0] = CvScalar.new(255, 0, 0)
+    minf = mat.normalize(1, 0, CV_NORM_INF, mask)
+    expected = [0.0, 0.0, 1.0, 0.0]
+    expected.each_with_index { |x, i|
+      assert_in_delta(x, minf[i][0], 0.001)
+    }
+
     assert_raise(TypeError) {
       mat.normalize(DUMMY_OBJ, 0, CV_NORM_INF)
     }
@@ -2032,6 +2041,9 @@ class TestCvMat < OpenCVTestCase
     assert_raise(TypeError) {
       mat.normalize(1, 0, DUMMY_OBJ)
     }
+    assert_raise(TypeError) {
+      mat.normalize(1, 0, CV_NORM_INF, DUMMY_OBJ)
+    }
   end
 
   def test_count_non_zero