Objective To establish a gas chromatography( GC) method for simultaneous determination of three residual solvents [ formic acid, ethanol and N, N-dimethylformamide( DMF) ] in carmustine raw materials. Methods HP-FFAP capillary column was used with nitrogen as the carrier gas and FID detector. The inlet temperature was 200 ℃,the detector temperature was 230 ℃,temperature programmed. The three residual solvents were determined by direct injection with methanol as solvent. Results The formic acid,ethanol and DMF had good linear relationships in their respective concentration ranges( r > 0. 99). The average recovery rates of formic acid,ethanol and DMF were more than 98. 0%( n = 9). Conclusion This method improves the sensitivity of formic acid and DMF by direct injection. It is easy to operate,and it has low cost,accurate results and good repeatability,which can better control the quality of carmustine.