diff --git a/funannotate/mask.py b/funannotate/mask.py
index c87fd80..2175ac3 100755
--- a/funannotate/mask.py
+++ b/funannotate/mask.py
@@ -125,10 +125,11 @@ def __init__(self, prog):
     args = parser.parse_args(args)
 
     # create log file for Repeats(capture stderr)
-    log_name = 'funannotate-mask.log'
+    # make this filename unique so multiple mask runs can happen in same folder
+    log_name = "funannotate-mask." + str(uuid.uuid4())[-8:] + ".log"
+    # this next seems unncessary as filenames should be unique but will leave in
     if os.path.isfile(log_name):
         os.remove(log_name)
-
     # initialize script, log system info and cmd issue at runtime
     lib.setupLogging(log_name)
     cmd_args = " ".join(sys.argv)+'\n'
@@ -197,6 +198,5 @@ def __init__(self, prog):
             lib.SafeRemove(tmpdir)
     print("-------------------------------------------------------")
 
-
 if __name__ == "__main__":
     main(sys.argv[1:])