Abstract: A new synthetic process of pentazocine has been developed. Starting from 3, 4-dimethylpyridin and benzyl chloride, via quaternarization, Grignard reaction addition/reduction/salt, cyclization, hydrogenation, alkylation and recrystallization, pentazocine were obtained in a total yield of 8. 4%(with a molar mass of 3, 4-dimethylpyridin), with purity greater than 99. 97%. The improved synthetic route is suitable for industrial production.