diff --git a/m3u8downloader/__init__.py b/m3u8downloader/__init__.py
index 722515271fb7bb96fecc18d2c8e87f8dd71a3a57..43a1e95ba4f9f4b02b5b315de1ecd3d1685ad6c8 100644
--- a/m3u8downloader/__init__.py
+++ b/m3u8downloader/__init__.py
@@ -1 +1 @@
-__version__ = "0.5.2"
+__version__ = "0.5.3"
diff --git a/m3u8downloader/main.py b/m3u8downloader/main.py
index d2dbe2012531dc1ded7e0bdf27cb312dc8186c16..e0683b13edf3ecf483944a04bb2b4c0cd8eea580 100644
--- a/m3u8downloader/main.py
+++ b/m3u8downloader/main.py
@@ -343,6 +343,7 @@ class M3u8Downloader:
 def main():
     parser = argparse.ArgumentParser(description="download video at m3u8 url")
     parser.add_argument('--version', action='store_true', help='print version')
+    parser.add_argument('--debug', action='store_true', help='enable debug log')
     parser.add_argument('--output', '-o', help='target video filename')
     parser.add_argument(
         '--tempdir', default=os.path.join(get_default_cache_dir(),
@@ -361,6 +362,9 @@ def main():
         parser.print_help()
         sys.exit(1)
 
+    if args.debug:
+        logging.getLogger("").setLevel(logging.DEBUG)
+
     SESSION.headers.update({'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.119 Safari/537.36'})
     downloader = M3u8Downloader(args.url, args.output, args.tempdir)
     downloader.start()
diff --git a/operational b/operational
index 1d5862ac3786f6dc3efcfe7d91e06c87edf5a23c..3ab6ee2660ae73a778473cb9b2446443cac585fe 100644
--- a/operational
+++ b/operational
@@ -39,8 +39,8 @@ to handle it on ryzen5.
 
 * current                                                             :entry:
 ** 
-** 2019-03-07 support --debug argument. change root log level to debug in that case.
 * done                                                                :entry:
+** 2019-03-07 support --debug argument. change root log level to debug in that case.
 ** 2019-03-07 make default cache dir work on windows.
 ** 2019-03-07 honor $XDG_CACHE_HOME
 ** 2019-03-03 add progress tracking log.