Abstract: The paper studied the method of determining 3MCPD in food by GC/ECD and GC/MS.Samples and Extrelut were filled into the column before mixed equably,and then extracted with diethyl ether instead of ethyl acetate.The sample was clarified by Florisil and derived for 30 minutes with TFAA under normal temperature,then determined with GC/ECD and GC/MS.There was a great innovation in the method of the clarification of Florisil.Certain ratio of diethyl ether-hexane was used to wash off the impurity during the clarification of Extrelut and Florisil.TFAA replaced HFBI to derive 3MCPD.The rate of recovery and variation coefficient was 80.6-117% and 6.5-10.1% when the content of chloropropanol ranged from 0.01mg/kg to 0.50mg/kg,the minimum detection of 3MCPD was 3μg/kg.This method is precise and stable.It can be applied to the determination of 3MCPD in the seasonings of meat products,beer,HVP and soy et al.