Abstract: One-step extraction with polar and nonpolar mixed solvents was a method of effective comprehensive extraction for antioxidant and essential oil of rosemary (Rosmarinus officinalis L.). The method was simple on operation and was easily put into practice. The reasonable conditions of comprehensive extraction for antioxidant and essential oil of rosemary were petroleum ether-ethanol-water of volume fraction 80:15:5 as mixed solvent, 10 folds of mass fraction of mixed solvent to rosemary leaves, 3 h for extraction at 80℃. The yield of rosemary oil was 2%-3%. The constituent analysis of rosemary oil showed that the essential oil mainly contains α-pinene, 1,8-cineole, camphene, camphor, verbenone, borneol, terpinen-4-ol, limonene, and bornyl acetate. The average yield of rosemary antioxidant was 16.98%. The main active components of rosemary antioxidant were carnosic acid, carnosol, and rosmarinic acid, whose contents were 15.17%, 2.51% and 5.62%, respectively.