An analytical method was established for the determination of β-agonists（e.g.terbutaline，salbutamol，cimbuterol，ractopamine，clenbuterol，brombuterol，mabuterol）residues in animal tissue by ultra high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry（UHPLC-Q-TOF-MS）.The samples were extracted with ammonium acetate，and determined by UHPLC-Q-TOF-MS after solid phase extraction.By software，the targeted compound was confirmed by the diff between theoretical accurate relative molecular mass（Mr） and the actual accurate Mr，element composition analysis，retention time，isotopic abundance model and product ion characteristics.The result indicated that the average recoveries were in the range of 75%-114% with relative standard deviations of 4.5%- 20.6%.The calibration curves were linear in the ranges of 0.4-40.0 μg/kg for clenbuterol，and 0.2-40.0 μg/kg for the rest of the compounds，with correlation coefficients of 0.991 4-0.999 9.The limits of quantitation were 0.4 μg/kg for clenbuterol and 0.2 μg/kg for the other compounds.