diff --git a/ThinkPHP/Library/Think/Model.class.php b/ThinkPHP/Library/Think/Model.class.php
index df50e0054..8b31c42ad 100644
--- a/ThinkPHP/Library/Think/Model.class.php
+++ b/ThinkPHP/Library/Think/Model.class.php
@@ -925,7 +925,7 @@ public function setInc($field, $step = 1, $lazyTime = 0)
                 $step = '-' . $step;
             }
         }
-        return $this->setField($field, array('exp', $field . '+' . $step));
+        return $this->setField($field, array('exp', '`' . $field . '`+' . $step));
     }
 
     /**
@@ -949,7 +949,7 @@ public function setDec($field, $step = 1, $lazyTime = 0)
                 $step = '-' . $step;
             }
         }
-        return $this->setField($field, array('exp', $field . '-' . $step));
+        return $this->setField($field, array('exp', '`' . $field . '`-' . $step));
     }
 
     /**