diff --git a/avocado/utils/process.py b/avocado/utils/process.py
index 529d73e441d7fc4a6eaa9f09c4e71e629332626c..04242acf6f4740a15da84f58ac78bc5baac60dc0 100644
--- a/avocado/utils/process.py
+++ b/avocado/utils/process.py
@@ -153,7 +153,7 @@ class SubProcess(object):
             output_file = self.stdout_file
             lock = self.stdout_lock
         elif input_pipe == self.sp.stderr:
-            prefix = '[stdout] %s'
+            prefix = '[stderr] %s'
             output_file = self.stderr_file
             lock = self.stderr_lock