Asafoetida is an oleo-gum-resin obtained from the exudates of the roots of the Iranian endemic medicinal plant, F. asafoetida. It is used widely all over the world as a flavoring spice in a variety of foods. was analysed by GC and GC/MS. The constituents were identified by their mass spectra and Kovats' indices. Among those, The main constituents were (E)-1-propenyl sec-butyl disulfide (58.9%), (Z)-β-ocimene (11.9%), (E)-β-ocimene (9.0%), β-pinene (5.0%) and (Z)-1-propenyl sec-butyl disulfide (3.9%).