The chemical components of the essential oil obtained from Artemisia lavandulaefolia DC. were analyzed by GC-MS. Ninety-nine compounds accounting for 94.9 % of the essential oil were identified. The major compounds in the essential oil were β-caryophyllene (16.1 %), cis-chrysanthenol (7.0 %), 1,8-cineole (5.6 %), borneol (5.3 %), trans-β-farnesene (5.1 %), camphor (4.9 %), yomogi alcohol (4.5 %), α-terpineol (3.9 %), and α-humulene oxide (3.3 %). The essential oil and some of its major compounds were tested for antimicrobial activity against 15 different genera of oral bacteria. The essential oil of A. lavandulaefolia exhibited considerable inhibitory effects against all obligate anaerobic bacteria (MIC values, 0.025 to 0.05 mg/mL; MBC values, 0.025 to 0.1 mg/mL) tested, while its major compounds demonstrated different degrees of growth inhibition.