diff --git a/tools/rosbag/scripts/fix_msg_defs.py b/tools/rosbag/scripts/fix_msg_defs.py
index 1ba056c323..0f5b2256a8 100755
--- a/tools/rosbag/scripts/fix_msg_defs.py
+++ b/tools/rosbag/scripts/fix_msg_defs.py
@@ -35,6 +35,7 @@
 
 import sys
 import rosbag.migration
+import roslib.message
 
 if __name__ == '__main__':
     if len(sys.argv) != 3: