The chemical composition of the essential oil from Heracleum rechingeri was analysed using GC-MS. Twenty-seven compounds, accounting for 94.62% of the extracted essential oil, were identified. The main oil compounds were octyl acetate (29.49%), elemicine (23.06%), (E)-caryophyllene (9.26%), caryophyllene oxide (6.42%), terpinolene (6.12%) and (Z)-3-octenyl acetate (4.72%). The antimicrobial activity of the essential oil was tested against three different bacteria by disc diffusion method and showed maximum inhibitory activity against Gram-positive bacteria, especially Bacillus subtilis.