Abstract: Molecular distillation was used for the further purification of the volatile oil from roots of valeriana officinalis L.var.latifolia Miq.The best process parameters, including temperature, feed rate, and scraping rate, of molecular distillation technique for separating the volatile oil were studied by response surface methodology based on single factor experiment.The content was detected by GC under the conditions of elastic quartz capillary column TR-5, detector temperature 250 ℃, gasification temperature 250 ℃, distributary refer 50 ∶ 1. The optimal extraction processing parameters were material-feeding rate of82 m L/h, distillation temperature of 68 ℃ and scraping rate of 188 r/min.Under the optimal processing conditions, the quality of volatile oil was markedly improved, and the content of bornyl acetate was 77.46%. The molecular distillation technique that could get the product with higher content of bornyl acetate has a very good prospect in industry.