Abstract: A method of headspace gas chromatography for the determination of 1,2-epoxypropane in water was described. The influencing factors such as chromatographic column,sampling volume, equilibrium temperature, equilibrium time were discussed. 25 mL water was injected into the 45 mL headspace bottle and heated 25 min at 40 ℃. Determination was performed on chromatographic column HP-1(60 m×0.53 mm×5 μm) at 60 ℃. Good linearities were observed in the range from 0.20 mg/L to 40.0 mg/L. The detection limit was about 0.05 mg/L . Characteristics of this method are sensitive and with less interference.