diff --git a/src/config.c b/src/config.c
index 2117758a..85085062 100644
--- a/src/config.c
+++ b/src/config.c
@@ -353,6 +353,7 @@ void loadServerConfigFromString(char *config) {
                 goto loaderr;
             }
         } else if (!strcasecmp(argv[0],"masterauth") && argc == 2) {
+            zfree(server.masterauth);
             server.masterauth = zstrdup(argv[1]);
         } else if (!strcasecmp(argv[0],"slave-serve-stale-data") && argc == 2) {
             if ((server.repl_serve_stale_data = yesnotoi(argv[1])) == -1) {