Abstract: A GC/MS method for determining the content of nicotine in tobacco flavor or casing was developed. Ten flavor samples and ten casing samples were determined by the developed method. The results showed that: the linear range of the method was from 0.9242 to 46.2080 μ g/mL (r=0.99992). The recoveries ranged from 97.54% to 99.14% and RSD was 1.34%. This method was reliable, sensitive and accurate in qualitative and quantitative analyses, and appropriate to determine the nicotine content in tobacco flavor and casing.