OBJECTIVE：To compare th e difference of the components of volatile oil in Citrus medica from different producing areas. METHODS ：The volatile oil of C. medica from 10 different producing areas was extracted with steam distillation ，and the yield was calculated. The components of the volatile oil of C. medica from different producing areas were analyzed by GC-MS. The compounds were retrieved from NIST 14.L mass spectrum database and identified. Relative mass fraction of chemical component was determined by peak area normalization method. Cluster analysis of samples were performed by using SPSS 20.0 software. RESULTS：The yields of volatile oil of C. medica from 10 different producing areas were 0.10％-1.75％，among which sample from Qianwei county in Leshan city of Sichuan province was the highest （1.75％）. A total of 66 components were identified in the volatile oil of C. medica from different producing areas ，with a relative molecular weight of 126.20-392.66. The majority was C 10 and C 15 compounds；isomers with relative molecular weight of 136，154 took up the great proportion ，which were mainly cycloalkane monoterpenes. There were 12 common components in the volatile oil of C. medica from different areas ，which were limonene（24.90％），terpinene（14.71％），（－）-4 terpineol（2.88％），citral（2.33％），α-myrrhene（2.33％），geraniol（1.52％）， α-pinene（1.37％），trans bergamot olene （1.16％），isoterpinene（1.13％），methyl palmitate （1.12％），linalool（1.09％）and geranyl acetate（1.04％）according to relative mass fraction ；8 of them were monoterpenes ，2 were sesquiterpenes and 2 were esters. There were 4 categories of C. medica from different producing areas ，i.e. S 2，S4，S6 clustered into one ；S1，S3，S7，S8 clustered into one ； S5 and S 10 clustered into one ；S9 as one . CONCLUSIONS ： There are some difference of the components in volatile oil of medica from different producing areas ，and the content of the same component also has great difference in the volatile oil of C. medica from different producing areas.