Water samples containing acrylamide were filtered and acidized by formic acid, then directly injected and finally detected by ultra performance liquid chromatography coupled with triple quadrupole mass spectrometry. Qualitative and quantitative analysis by external standard were achieved by electrospray ionization in positive mode using multiple reaction monitoring. The limit of determination for acrylamide in drinking water was 0.15mg/L. The average recovery rate of real samples was in the range of 92%~123%. This method was environment friendly, simple and sensitive.