diff --git a/mysql-test/r/func_str.result b/mysql-test/r/func_str.result
index 5a582f08829..d3757f799ce 100644
--- a/mysql-test/r/func_str.result
+++ b/mysql-test/r/func_str.result
@@ -2789,7 +2789,7 @@ DROP TABLE t1;
 #
 SELECT CONV(1,-2147483648,-2147483648);
 CONV(1,-2147483648,-2147483648)
-
+NULL
 #
 # End of 5.5 tests
 #
diff --git a/sql/item_strfunc.cc b/sql/item_strfunc.cc
index c6e9384bc5e..a0fdb3cf811 100644
--- a/sql/item_strfunc.cc
+++ b/sql/item_strfunc.cc
@@ -2954,7 +2954,10 @@ String *Item_func_conv::val_str(String *str)
 
   if (!(ptr= longlong2str(dec, ans, to_base)) ||
       str->copy(ans, (uint32) (ptr - ans), default_charset()))
-    return make_empty_result();
+  {
+    null_value= 1;
+    return NULL;
+  }
   return str;
 }