diff --git a/modules/flann/include/opencv2/flann/lsh_table.h b/modules/flann/include/opencv2/flann/lsh_table.h
index cb9e05fa26..126fb2a992 100644
--- a/modules/flann/include/opencv2/flann/lsh_table.h
+++ b/modules/flann/include/opencv2/flann/lsh_table.h
@@ -193,7 +193,7 @@ public:
     void add(Matrix<ElementType> dataset)
     {
 #if USE_UNORDERED_MAP
-        if (!use_speed_) buckets_space_.rehash((buckets_space_.size() + dataset.rows) * 1.2);
+        buckets_space_.rehash((buckets_space_.size() + dataset.rows) * 1.2);
 #endif
         // Add the features to the table
         for (unsigned int i = 0; i < dataset.rows; ++i) add(i, dataset[i]);