Objective A ultra performance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS) was developed for the simultaneous determination of 2,4,5-trichlorophenol, 2,4,5-trichlorophenoxyacetic acid and pentachlorophenol in edible lard. Methods The edible lard samples were extracted by 80% acetonitrile, then puried with solid phase extraction(SPE)and exane, and loaded on a Atlantis T3 column (2.1 mm×150 mm,3 μm). Acetonitrile-5.0 mmol/L ammonium acetate solution was used as the mobile phase for gradient elution.The compounds were detected by UPLC-MS/MS with negative electrospray ion source (ESI-) under multiple reaction monitoring mode. The matrix-matched external standard method was used for quantitation. Results 2,4,5-trichlorophenol, 2,4,5-trichlorophenoxyacetic acid and pentachlorophenol had an excellent linear relationship in the range of 2.0-100.0 μg/L with correlation coefficient (r) above 0.999. The limits of detection were 0.09,1.59 and 0.90 μg/kg, and the quantification limits were 0.29,5.28 and 3.00 μg/kg. The recoveries of the three compounds ranged from 71.9%-109.5% with relative standard deviation of 0.2%-9.2% (n=6). Conclusion The method was simple,sensitive and accurate, and was suitable for high-throughput detection for 2,4,5-trichlorophenol, 2,4,5-trichlorophenoxyacetic acid and pentachlorophenol in edible lard.