diff --git a/locust/main.py b/locust/main.py
index cdb09db194..a3c404e15b 100644
--- a/locust/main.py
+++ b/locust/main.py
@@ -238,6 +238,7 @@ def is_valid_percentile(parameter):
                 # remove options that dont make sense on worker
                 options.run_time = None
                 options.autostart = None
+                options.csv_prefix = None
                 break
         else:
             # we're in the parent process