Abstract Gum of Ferula assa-foetida was collected from Kerman province (center of Iran) in summer 1996. The essential oil was obtained by water-steam distillation (17%) and 13 components were identified by GC and GC/MS. The main constituents were (E)-1-propenyl sec-butyl disulfide (58.9%), (Z)-Î²-ocimene (11.9%), (E)-Î²-ocimene (9.0%), Î²-pinene (5.0%) and (Z)-1-propenyl sec-butyl disulfide (3.9%).