diff --git a/itchatmp/log.py b/itchatmp/log.py
index 1843505..078c675 100644
--- a/itchatmp/log.py
+++ b/itchatmp/log.py
@@ -31,6 +31,8 @@ def set_logging(self, showOnCmd=True, loggingFile=None,
                 self.fileHandler.close()
             if loggingFile is not None: # add new fileHandler
                 self.fileHandler = logging.FileHandler(loggingFile)
+                formatter = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
+                self.fileHandler.setFormatter(formatter)
                 self.logger.addHandler(self.fileHandler)
             self.loggingFile = loggingFile
         if loggingLevel != self.loggingLevel: