diff --git a/FHEM/42_SMARTMON.pm b/FHEM/42_SMARTMON.pm
index 952b0279d..60c48f0b8 100644
--- a/FHEM/42_SMARTMON.pm
+++ b/FHEM/42_SMARTMON.pm
@@ -29,6 +29,7 @@ package main;
 
 use strict;
 use warnings;
+use JSON;
 use Data::Dumper;
 
 my $VERSION = "0.9.9";