diff --git a/library/think/log/driver/File.php b/library/think/log/driver/File.php
index 11b265a2..bb6844a9 100644
--- a/library/think/log/driver/File.php
+++ b/library/think/log/driver/File.php
@@ -58,7 +58,7 @@ class File
         }
 
         $runtime    = number_format(microtime(true) - THINK_START_TIME, 10);
-        $reqs       = number_format(1 / $runtime, 2);
+        $reqs       = $runtime > 0 ? number_format(1 / $runtime, 2) : '∞';
         $time_str   = ' [运行时间：' . number_format($runtime, 6) . 's][吞吐率：' . $reqs . 'req/s]';
         $memory_use = number_format((memory_get_usage() - THINK_START_MEM) / 1024, 2);
         $memory_str = ' [内存消耗：' . $memory_use . 'kb]';