Abstract The composition of the essential oil obtained from the dried flowering aerial parts of Verbascum thapsus L. was analyzed by GC and GC-MS. Ninety-two components were identified in the essential oil of V. thapsus. The major components of the essential oil were 6,10,14-trimethyl-2-pentadecanone (14.3 %) and (E)-phytol (9.3 %). The antimicrobial activity of V. thapsus oil was studied using the disk diffusion method and determination of minimal inhibitory concentration (MIC) values. The V. thapsus oil exhibited concentration-dependent antimicrobial activity against Bacillus subtilis, Staphylococcus aureus, Salmonella typhi, Pseudomonas aeruginosa and Aspergilus niger. The essential oil did not show any antimicrobial activity against Escherichia coli and Candida albicans.