diff --git a/src/tree/updater_colmaker.cc b/src/tree/updater_colmaker.cc
index 26efb33bc002..d034fa56675d 100644
--- a/src/tree/updater_colmaker.cc
+++ b/src/tree/updater_colmaker.cc
@@ -292,7 +292,7 @@ class ColMaker: public TreeUpdater {
           float fsplit;
           if (tid != 0) {
             if (std::abs(stemp[tid - 1][nid].last_fvalue - e.first_fvalue) > rt_2eps) {
-              fsplit = (stemp[tid - 1][nid].last_fvalue - e.first_fvalue) * 0.5f;
+              fsplit = (stemp[tid - 1][nid].last_fvalue + e.first_fvalue) * 0.5f;
             } else {
               continue;
             }