diff --git a/modules/imgproc/src/lsd.cpp b/modules/imgproc/src/lsd.cpp
index 6138cfce7e..0e82a39029 100644
--- a/modules/imgproc/src/lsd.cpp
+++ b/modules/imgproc/src/lsd.cpp
@@ -1198,7 +1198,6 @@ int LineSegmentDetectorImpl::compareSegments(const Size& size, InputArray lines1
     _lines1 = lines1.getMat();
     _lines2 = lines2.getMat();
     // Draw segments
-    std::vector<Mat> _lines;
     for(int i = 0; i < _lines1.size().width; ++i)
     {
         Point b(_lines1.at<Vec4i>(i)[0], _lines1.at<Vec4i>(i)[1]);
diff --git a/modules/objdetect/src/erfilter.cpp b/modules/objdetect/src/erfilter.cpp
index dc8f18caf6..e942094b1d 100644
--- a/modules/objdetect/src/erfilter.cpp
+++ b/modules/objdetect/src/erfilter.cpp
@@ -2934,7 +2934,6 @@ void erGrouping(InputArrayOfArrays _src, vector<vector<ERStat> > &regions, const
             float a1=((int)meaningful_clusters.at(i).size()*sumxy-sumx*sumy) /
                ((int)meaningful_clusters.at(i).size()*sumx2-sumx*sumx);
 
-            vector<float> data;
             if (a1 != a1)
                 data_arrays.at(i).push_back(1.f);
             else
diff --git a/modules/video/perf/opencl/perf_optflow_pyrlk.cpp b/modules/video/perf/opencl/perf_optflow_pyrlk.cpp
index b2492e1141..1d7e643d52 100644
--- a/modules/video/perf/opencl/perf_optflow_pyrlk.cpp
+++ b/modules/video/perf/opencl/perf_optflow_pyrlk.cpp
@@ -83,9 +83,7 @@ OCL_PERF_TEST_P(PyrLKOpticalFlowFixture, PyrLKOpticalFlow,
     const PyrLKOpticalFlowParams params = GetParam();
     const int pointsCount = get<0>(params);
 
-    vector<Point2f> pts, nextPts;
-    vector<unsigned char> status;
-    vector<float> err;
+    vector<Point2f> pts;
     goodFeaturesToTrack(frame0, pts, pointsCount, 0.01, 0.0);
     Mat ptsMat(1, static_cast<int>(pts.size()), CV_32FC2, (void *)&pts[0]);
 
@@ -99,4 +97,4 @@ OCL_PERF_TEST_P(PyrLKOpticalFlowFixture, PyrLKOpticalFlow,
 
 } } // namespace cvtest::ocl
 
-#endif // HAVE_OPENCL
\ No newline at end of file
+#endif // HAVE_OPENCL