diff --git a/src/Illuminate/Session/Store.php b/src/Illuminate/Session/Store.php
index bf77ee3568ff..9da31a334fe9 100644
--- a/src/Illuminate/Session/Store.php
+++ b/src/Illuminate/Session/Store.php
@@ -159,7 +159,10 @@ protected function isInvalid($session)
 	{
 		if ( ! is_array($session)) return true;
 
-		return (time() - $session['last_activity']) > ($this->lifetime * 60);
+		return ( $this->lifetime === 0 
+		         ? false 
+		         : (time() - $session['last_activity']) > ($this->lifetime * 60) 
+		);
 	}
 
 	/**
@@ -623,4 +626,4 @@ public function offsetUnset($key)
 		$this->forget($key);
 	}
 
-}
\ No newline at end of file
+}