diff --git a/module/task/lang/en.php b/module/task/lang/en.php
index f25e133a6b..8416b24dc3 100644
--- a/module/task/lang/en.php
+++ b/module/task/lang/en.php
@@ -146,6 +146,7 @@ $lang->task->confirmRecord         = '"Left" is zero, this task will be done. Ar
 
 $lang->task->error = new stdclass();
 $lang->task->error->consumedNumber   = '"Consumed" must be number';
+$lang->task->error->estimateNumber   = '"Estimate" must be number';
 $lang->task->error->consumedSmall    = '"Consumed" must be more than consumed before';
 $lang->task->error->consumedThisTime = 'Please input "hours"';
 $lang->task->error->left             = 'Please input "left"';
diff --git a/module/task/lang/zh-cn.php b/module/task/lang/zh-cn.php
index 7a04edccc0..2c8fdced7e 100644
--- a/module/task/lang/zh-cn.php
+++ b/module/task/lang/zh-cn.php
@@ -146,6 +146,7 @@ $lang->task->confirmRecord         = '"剩余"为0，任务将标记为"已完
 
 $lang->task->error = new stdclass();
 $lang->task->error->consumedNumber   = '"已经消耗"必须为数字';
+$lang->task->error->estimateNumber   = '"预计剩余"必须为数字';
 $lang->task->error->consumedSmall    = '"已经消耗"必须大于之前消耗';
 $lang->task->error->consumedThisTime = '请填写"工时"';
 $lang->task->error->left             = '请填写"剩余"';
diff --git a/module/task/model.php b/module/task/model.php
index eb44ed9b67..9c1d64acef 100644
--- a/module/task/model.php
+++ b/module/task/model.php
@@ -93,6 +93,15 @@ class taskModel extends model
         $now   = helper::now();
         $tasks = fixer::input('post')->get();
         $mails = array();
+
+        /* check estimate. */
+        for($i = 0; $i < $this->config->task->batchCreate; $i++)
+        {
+            if(!empty($tasks->name[$i]) and !preg_match("/^[0-9]+(.[0-9]{1,3})?$/", $tasks->estimate[$i]))
+            {
+                die(js::alert($this->lang->task->error->estimateNumber));
+            }
+        }
         for($i = 0; $i < $this->config->task->batchCreate; $i++)
         {
             if(empty($tasks->name[$i])) continue;