[Objective]The research aimed to study the determination of 16 kinds of OCPs in water by liquid-liquid extraction- GC.[Method] The new method for determining 16 kinds of OCPs in water by liquid-liquid extraction- GC was established,and the influencing factors such as nitrogen pressure and water bath temperature were discussed.[Result]Detection limit of the method was from 3.2 to 14.1 ng /L,the relative standard deviation was between 4.0% and 9.6%,and the average recovery ranged from 80.8% to 106.0%.By optimizing nitrogen pressure and water bath temperature in the sample pretreatment process,when nitrogen pressure was ±0.087 kPa,and water bath temperature was ±36 ℃,recovery effect of this method was better.[Conclusion]The determination method had accurate qualitative and quantitative results,and met detection requirement of 16 kinds of OCPs in water.