Abstract The composition of the volatile oil of Brassica oleracea L. var. gongylodes seeds was analyzed by GC/MS and retention indices. The main constituents of the oil were: 4-methylthiobutyl isothiocyanate (55.6%), 3-butenyl isothiocyanate (27.6%), allylisothiocyanate (5.4%), 5-methylthiopentanitrile (3.4%), 3-mediylthiopropylisothiocyan ate (2.6%) and 2-phenylethyl isothiocyanate (2.4%).