Abstract: A method for simultaneous determination of deoxynivalenol, 3-Acetyl deoxynivalenol, 15-Acetyl deoxynivalenol and zearalenone in pastry had been developed by high performance liquid chromatography-tandem mass spectrometry ( HPLC-MS/MS) .The determination was finished within 4 minutes.The results showed that all of the 4 mycotoxins had good linearity in the range of 5¹000 μg/kg with the correlation coefficients ( R²) better than 0.997.The limits of detection ( LODs) of DON and ZEN were 1.0 μg/kg, 3-Ac DON and 15-Ac DON were 1.5 μg/kg. The results of 134 pastry samples determined by the method showed that all of the 4 mycotoxins were detected in the tested samples.The detection rate were 2.2%, 78.4%, 3.0% and 5.2%for ZEN, DON, 3-Ac DON and 15-Ac DON. The maximum residual contents were lower than national food safety limited requiements.