Abstract The essential oil of the dried flowering aerial parts of Stachys persica Gmel. (Labiatae) collected from the suburb of Nour, Mazandaran Province, North of Iran, in May 2007, were isolated by hydrodistillation and analyzed by means of GC and GC/MS. The major components of S. persica oil were pinocamphone (25.6%), (E)-Î²-farnesene (6.3%) and hexadecanoic acid (6.2%). The antimicrobial activity of S. persica oil was studied using the disk diffusion method and determination of minimal inhibitory concentration (MIC) values against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typhi, Pseudomonas aeroginosa, Aspergilus niger and Candida albicans. The S. persica oil exhibited concentration-dependent antimicrobial activity on Bacillus subtilis, Aspergilus niger and Candida albicans.