A gas chromatographic（GC） method was established for the analysis of a potential greenhouse gas，nitrous oxide（N2O） in wastewater treatment.The optimum conditions of chromatography were determined by a series of parallel tests.The working temperatures of the injector，column and electron capture detector（ECD） were 105，100 and 300 ℃，respectively；95% Ar +5% CH4 was selected as the carrier gas；the column flow and the makeup gas flow were 25 mL/min and 50 mL/min，respectively.Under the optimal conditions，the calibration curve was linear in the range of 0.255-100 mg/L N2O，with correlation coefficient higher than 0.999 and the mean recovery larger than 90%.When detecting 100 mg/L N2O（standard samples） using direct injection and headspace methods，the relative standard deviation（RSD） values were 1.5% and 0.32%，respectively，and the recoveries were both over 90%.The method was successfully applied in the determination of N2O in wastewater treatment processes and the detected values are consistent with the results reported in literatures.This method is simple，sensitive and repeatable.