diff --git a/common/utils.py b/common/utils.py
index 59723fa..5a08d10 100644
--- a/common/utils.py
+++ b/common/utils.py
@@ -753,12 +753,18 @@ def ping_avg_time(nameserver):
             logger.log('ALERT', f'100.0% packet loss, ping {nameserver} failed.')
             return None
         elif platform.system() in ('Darwin', 'Linux'):
-            avg_time = re.findall(r'(?:min/avg/max/.+ )(?:\d+\.\d+)/(\d+\.\d+)/', text)[0]
-            logger.log('INFOR', f'ping {nameserver} average time {avg_time} ms.')
+            try:
+                avg_time = re.findall(r'(?:min/avg/max/.+ )(?:\d+\.\d+)/(\d+\.\d+)/', text)[0]
+                logger.log('INFOR', f'ping {nameserver} average time {avg_time} ms.')
+            except IndexError:
+                return None
             return avg_time
         elif platform.system() == 'Windows':
-            avg_time = re.findall(r'(?:Average|平均).+(\d.)ms', text)[0]
-            logger.log('INFOR', f'ping {nameserver} average time {avg_time} ms.')
+            try:
+                avg_time = re.findall(r'(?:Average|平均).+(\d.?)ms', text)[0]
+                logger.log('INFOR', f'ping {nameserver} average time {avg_time} ms.')
+            except IndexError:
+                return None
             return avg_time
         else:
             logger.log('ALERT', f'{text}')