diff --git a/src/image.cpp b/src/image.cpp
index 85064b62b8..3b71d64e16 100644
--- a/src/image.cpp
+++ b/src/image.cpp
@@ -1672,6 +1672,7 @@ int ColorMap::reset(int narg, char **arg)
 
   nentry = force->inumeric(FLERR,arg[4]);
   if (nentry < 1) return 1;
+  delete [] mentry;
   mentry = new MapEntry[nentry];
 
   int n = 5;