Abstract: UHPLC-MS/MS was applied to the simultaneous determination of 3 microcystic algae toxins (MC-RR, MC-LR and MC-YR ) in field snail. The field snail sample was extracted with methanol (85+15) solution and purified by passing through Oasis HLB-solid phase extraction column. UPLC BEH C18 column was used as stationary phase, and mixtures of (A) formic acid (0.1+99.9) aq. solution and (B) mixture of methanol-acetonitrile (1+1) solution mixed in different ratios were used as mobile phase in gradient elution. ESI+ as well as multi-reactions monitoring was adopted in MS/MS. Linear relationships between values of peak area and mass concentration of the 3 microcystic algae toxins were kept in the same range of 1.0-100.0 μg·L-1, with detection limits (3S/N) in the range of 0.05-0.08 μg·kg-1. On the base of blank sample, test for recovery was made by standard addition method; values of recovery found were in the range of 67.3%-84.2%, with RSD′s (n=6) in the range of 6.1%-8.3%.