A high performance liquid chromatographic（HPLC） method was established for the simultaneous determination of four kinds of prohibited aldehyde and ketone compounds（crotonaldehyde,acetophenone,2,4 dihydroxy 3 methylbenzaldehyde and 2 pentylidene cyclohexanone） in cosmetics.The samples were extracted with 50% acetonitrile solution,then separated on an AQ-C18（46 mm×150 mm,5 μm） column and detected by HPLC with a diode array detector.The retention time and UV absorption spectra were adopted for qualitation and the external standard method was used for quantitation.The positive cosmetic samples were confirmed by HPLC-MS/MS method.Under the optimal conditions,the results showed that four analytes showed good linearities in the range of 005-20 mg/L with correlation coefficients not less than 0999 9.The limits of detection and quantitation were in the ranges of 05-10 mg/kg and 15-30 mg/kg,respectively.The mean recoveries for the samples at three spiked levels ranged from 890% to 1067% with the relative standard deviations（RSDs,n=6） of 20%-69%.The method is accurate and reliable,and is suitable for the determination of four kinds of prohibited aldehyde and ketone compounds in cosmetics.