A method was developed for the simultaneous determination of 72 veterinary residues in shrimps by QuEChERS and high performance liquid chromatography tandem mass spectrometry. The sample was extracted with 5% acetic acid - acetonitrile, and the supernatant liquid was directly purified with C18, meanwhile, acetonitrile was used for the precipitation of protein. The extract was evaporated under nitrogen stream, and redissolved with 1 mL 0. 1% formic acid - acetonitrile(4 : 1). Prior to the injection into LC MS/MS, the sample was filtered through a 0. 22 μm filter mem-brane. The HPLC separation was performed on ZORBAX SB-C18 column by gradient elution with ace-tonitrile and 0. 1% formic acid as mobile phase. The analysis of target compounds was carried out with electrospray ionization(ESI) under multi-reaction monitoring( MRM) mode. The external stand-ard method was used for quantification. Under the optimal conditions, the correlation coefficients for 97. 2% of the veterinaries were larger than 0. 95 in the linear range of 0. 1 -1 840μg/kg, the limits of quantitation ranged from 0. 02 μg/kg to 33. 58 μg/kg. The recoveries of 72 veterinary at three spiked levels were between 61% and 119% , except that for dibutylsuccinate, cefapirin, cefqui-nome, ceftiofur, lincomycin ane diazinon were between 38% and 58% , and their relative standard deviations were in the range of 1. 6% -20% . The established method was used for the screening and determination of real samples(pteris shrimp, freshwater shrimp and sea shrimp) bought from super-market. It was shown that no residue was detected in the sea shrimp and pteris shrimp samples, and 4. 0 μg/kg of sulfadiazine as well as 2. 2 jig/kg of sulfamethoxazole were found in freshwater shrimp sample, but the concentrations were all lower than the MRLs.%建立了虾肉中72种兽药残留的QuEChERS结合液相色谱串联质谱测定的分析方法.样品经5％醋酸乙腈均质提取离心后,上清液依次用C18净化、乙腈沉淀蛋白、氮吹浓缩,0.1％甲酸-乙腈(4∶1,体积比)定容,0.22 μm滤膜过滤,LC - MS/MS测定,外标法定量.流动相为0.1％甲酸和乙腈,色谱柱为ZORBAXSB-C18,采用梯度洗脱模式进行色谱分离；离子源为电喷雾离子源(ESI),多重反应监测模式(MRM).在0.1～1 840 μ~kg范围内,97.2％的目标兽药的线性相关系数大于0.95,定量下限范围为0.02～ 33.58 μg/kg.除熊脱氧胆酸、头孢吡啉、头孢喹咪、头孢噻呋、林可霉素、二嗪哝的回收率为38％～58％外,其它目标化合物的回收率为61％- 119％,相对标准偏差为1.6％～20％,满足各国的限量法规要求.对市售的海虾、凤尾虾仁、青虾仁样品进行72种兽药残留筛查测定,海虾和凤尾虾仁中无检出；青虾仁样品中检出磺胺嘧啶和磺胺甲(口恶)唑,检出量分别为4.01μg/kg和2.2μg/kg,均低于各国规定的限量要求.
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