Abstract: Response surface analysis methodology( RSM) was used for optimizing ultrasound-assisted extraction of volatile oil from Litsea Cubeba. Based on single-factor experiments,three independent variables including extracting time,solvent-solidratio and ultrasound time,were selected as affecting factors during extraction. The experiments were arranged according to Box-Behnken central composite experiment design. Response surface analysis method was applied to determine the effect of central composite experiment design. The results showed that the optimum ultrasound extraction conditions for volatile oil from Litsea Cubeba were as follow: extraction time3.4h,ratio of liquid to solid 18∶1( m L/g) and ultrasound time 12 min.While the actual extraction yield was 5.33%.The volatile oil was analyzed by GC-MS,25 peaks were separated and 21 compounds which accounted for 98.97% of GC were identified. The result showed,that among 21 compounds,15 compounds are terpines. Among all of the chemical constituents of volatile oil from Litsea Cubeba,three isomers of Citral( z)-3,7-Dimethylocta-2,6-octadiena,( E)-3,7-Dimethyl-2,6-octadienal and 3,7-Dimethyl-2,6-octadiena were the characteristic aroma constituent for fruits of Litsea Cubeba.