Abstract: OBJECTIVE To establish a capillary GC method for the determination of residual organic solvents including methylene chloride, acetone, methanol, methyl tert-butyl ether, ethyl acetate and toluene in naltrexone methylbromide. METHODS The residual organic solvents were separated on DB-WAX capillary column (30.0 m×0.25 mm, 0.25 μm). FID was used as detector with a temperature of 250 ℃, and the inlet temperature was 240 ℃. The carrier gas was nitrogen, and the flow rate was 1.0 mL·min^-1. Column temperature was programmed set. RESULTS The six residual organic solvents consisting of methyl tert-butyl ether, acetone, ethyl acetate, methanol, methylene chloride and toluene were completely separated, the recovery rate and linear relationship were good, and three batches of samples coincided with the requirements. CONCLUSION The method is simple, accurate, sensitive and reproducible, it can be used for the determination of the residual organic solvents in naltrexone methylbromide.