diff --git a/modules/ml/test/test_mltests2.cpp b/modules/ml/test/test_mltests2.cpp
index b8c909001e..616a527bfe 100644
--- a/modules/ml/test/test_mltests2.cpp
+++ b/modules/ml/test/test_mltests2.cpp
@@ -721,5 +721,68 @@ void CV_MLBaseTest::load( const char* filename )
         CV_Error( CV_StsNotImplemented, "invalid stat model name");
 }
 
+
+
+TEST(TrainDataGet, layout_ROW_SAMPLE)  // Details: #12236
+{
+    cv::Mat test = cv::Mat::ones(150, 30, CV_32FC1) * 2;
+    test.col(3) += Scalar::all(3);
+    cv::Mat labels = cv::Mat::ones(150, 3, CV_32SC1) * 5;
+    labels.col(1) += 1;
+    cv::Ptr<cv::ml::TrainData> train_data = cv::ml::TrainData::create(test, cv::ml::ROW_SAMPLE, labels);
+    train_data->setTrainTestSplitRatio(0.9);
+
+    Mat tidx = train_data->getTestSampleIdx();
+    EXPECT_EQ((size_t)15, tidx.total());
+
+    Mat tresp = train_data->getTestResponses();
+    EXPECT_EQ(15, tresp.rows);
+    EXPECT_EQ(labels.cols, tresp.cols);
+    EXPECT_EQ(5, tresp.at<int>(0, 0)) << tresp;
+    EXPECT_EQ(6, tresp.at<int>(0, 1)) << tresp;
+    EXPECT_EQ(6, tresp.at<int>(14, 1)) << tresp;
+    EXPECT_EQ(5, tresp.at<int>(14, 2)) << tresp;
+
+    Mat tsamples = train_data->getTestSamples();
+    EXPECT_EQ(15, tsamples.rows);
+    EXPECT_EQ(test.cols, tsamples.cols);
+    EXPECT_EQ(2, tsamples.at<float>(0, 0)) << tsamples;
+    EXPECT_EQ(5, tsamples.at<float>(0, 3)) << tsamples;
+    EXPECT_EQ(2, tsamples.at<float>(14, test.cols - 1)) << tsamples;
+    EXPECT_EQ(5, tsamples.at<float>(14, 3)) << tsamples;
+}
+
+TEST(TrainDataGet, layout_COL_SAMPLE)  // Details: #12236
+{
+    cv::Mat test = cv::Mat::ones(30, 150, CV_32FC1) * 3;
+    test.row(3) += Scalar::all(3);
+    cv::Mat labels = cv::Mat::ones(3, 150, CV_32SC1) * 5;
+    labels.row(1) += 1;
+    cv::Ptr<cv::ml::TrainData> train_data = cv::ml::TrainData::create(test, cv::ml::COL_SAMPLE, labels);
+    train_data->setTrainTestSplitRatio(0.9);
+
+    Mat tidx = train_data->getTestSampleIdx();
+    EXPECT_EQ((size_t)15, tidx.total());
+
+    Mat tresp = train_data->getTestResponses();  // always row-based, transposed
+    EXPECT_EQ(15, tresp.rows);
+    EXPECT_EQ(labels.rows, tresp.cols);
+    EXPECT_EQ(5, tresp.at<int>(0, 0)) << tresp;
+    EXPECT_EQ(6, tresp.at<int>(0, 1)) << tresp;
+    EXPECT_EQ(6, tresp.at<int>(14, 1)) << tresp;
+    EXPECT_EQ(5, tresp.at<int>(14, 2)) << tresp;
+
+
+    Mat tsamples = train_data->getTestSamples();
+    EXPECT_EQ(15, tsamples.cols);
+    EXPECT_EQ(test.rows, tsamples.rows);
+    EXPECT_EQ(3, tsamples.at<float>(0, 0)) << tsamples;
+    EXPECT_EQ(6, tsamples.at<float>(3, 0)) << tsamples;
+    EXPECT_EQ(6, tsamples.at<float>(3, 14)) << tsamples;
+    EXPECT_EQ(3, tsamples.at<float>(test.rows - 1, 14)) << tsamples;
+}
+
+
+
 } // namespace
 /* End of file. */