Abstract: The residual dynamics and final residues of emamectin benzoate in paddy,rice,water and soil samples were determined by high performance liquid chromatography equipped with ultraviolet detector(HPLC-UVD).Water samples were extracted with methylene chloride and other samples were extracted with acetone/water (7∶ 3,V/V),the extracts were cleaned up by liquid-liquid extraction.Under the fortified level 0.050 to 1.0 mg/kg,the recovery ranged from 88.44% to 94.10% for water,86.29% to 101.1% for paddy,84.49% to 105.5% for rice,86.69% to 93.27% for soil with the relative standard deviations of 3.09% to 10.57% ,11.28% to 13.68% ,2.62% to 6.73% and 6.72% to 8.89% ,respectively.The limit of detection of the method was 0.018 mg/kg,the limit of quantification was 0.061 mg/kg for rice.The half-life of emamectin benzoate was 1.52 to 1.61 days in paddy,1.93 to 2.04 days in water and 2.01 to 2.14 days in soil,respectively.When sprayed for 4 successive times at application rate of 750 g/hm2,at interval time of 7 d after the last application,the final residues of emamectin benzoate in rice were lower than LOQ.