Abstract: Residual amounts of triazophos in water sample were determined by GC with nitrogen-phosphorus detector (NPD).Residual triazophos in water sample was extracted with benzene and separated on HP-5 capillary column (30 m×0.32 mm,0.25 μm).Linear relationship between values of peak area and mass concentration of triazophos was obtained in the range of 0.005-1.0 mg·L-1,with detection limit (3S/N) of 3.5 μg·L-1.Test for recovery was made by standard addition method,giving results in the range of 94.0%-97.5%.Values of RSD′s (n=6) found were less than 3.7%.