diff --git a/Classification/include/CGAL/Classification/Feature/Elevation.h b/Classification/include/CGAL/Classification/Feature/Elevation.h
index f261431913f..ce5858d7c85 100644
--- a/Classification/include/CGAL/Classification/Feature/Elevation.h
+++ b/Classification/include/CGAL/Classification/Feature/Elevation.h
@@ -105,7 +105,8 @@ public:
           mean += get(point_map, *(input.begin()+(*it))).z();
           ++ nb;
         }
-
+        if (nb == 0)
+          continue;
         mean /= nb;
         dem(i,j) = mean;
       }