A simple method for determining 33 pesticides with a wide polarity range (logKow 0.6-4.5) in aquatic products was developed based on LC-MS/MS.The target analytes included three types of widely used pesticides:insecticides,fungicides and herbicides.Based on the optimization of ultrasonic assisted extraction and GPC clean-up procedures,the matrix effect,extraction recoveries and LOD were improved distinctively.LOQ of this method was below 0.5 ng/g for all pesticides,which is superior to values in the literature,and the matrix effect was reduced effectively (-14.7％ to 7.5％).The method was successfully applied to investigate the pesticide residue levels of twenty-five samples including seven common kinds of fishes from Northeast China.The results showed that all targeted pesticides were present in the fish samples;however,their levels were low,except for atrazine,linuron,ethoprophos,tetrachlorvinphos,acetochlor and fenthion.Atrazine and linuron caught our attention because the concentrations of atrazine in fish samples from Liaoning province were in the range of 0.5-8 ng/g (w/w) with mean concentration of 2.3 ng/g,which were far above those of other pesticides.The levels of linuron were in the range of 0.6-6 ng/g (mean concentration 2.8 ng/g),which were the highest among all targeted pesticides in the Inner Mongolia.This is the first systematic investigation on the characteristics and levels of these pesticides in aquatic products from northeast China.Considering their toxicity and bioaccumulation,the potential risk of atrazine and linuron from consuming aquatic products should be paid more attention.