A method was established for the determination of α-zearalenol and zearalenone in cereal and oil food by high performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS）.Samples were extracted by chloroform,purified by sequence back extraction using sodium hydroxide solution and dichloromethane,quantitatively concentrated and measured by HPLC-MS/MS.The linear ranges of two target compounds were over 0.2~100 ng/mL and the correlation coefficient（r）＞0.99.The detection limits ofα-zearalenol and zearalenone were 1.5 μg/kg and 1.0 μg/kg,respectively.The mean recoveries of two target compounds ranged from 70.6% to 98.9% with RSD＜10%（n=6）.This method is sensitive,reproducible and suitable for determination of trace α-zearalenol and zearalenone in cereal and oil food.