The headspace gas chromatography method was used to determine the residual methanol,propylene oxide in poly(propylene carbonate).The results indicated that the linear ranges of methanol and propylene oxide were 0.025-0.400 g·L-1(r=0.9994) and 0.025-0.400 g·L-1(r=0.9997) respectively,the recoveries were 95.4%and 98.3%respectively,RSD were 3.7% and 1.8%(n=5) respectively.The method is simple,accurate and sensitive with good reproducibility,which can be used for determining of the residual methanol and propylene oxide in poly(propylene carbonate).