diff --git a/app/code/core/Mage/Cron/Model/Observer.php b/app/code/core/Mage/Cron/Model/Observer.php
index 27fea671b0b..c61739ac26a 100644
--- a/app/code/core/Mage/Cron/Model/Observer.php
+++ b/app/code/core/Mage/Cron/Model/Observer.php
@@ -220,7 +220,9 @@ public function cleanup()
 
         $now = time();
         foreach ($history->getIterator() as $record) {
-            if (strtotime($record->getExecutedAt()) < $now - $historyLifetimes[$record->getStatus()]) {
+            if (empty($record->getExecutedAt())
+                || (strtotime($record->getExecutedAt()) < $now - $historyLifetimes[$record->getStatus()])
+            ) {
                 $record->delete();
             }
         }