Abstract: In order to obtain the highest yield of oil from Hippophae rhamnoides Linn.seeds,orthogonal test of supercritical CO2 extraction was carried out to obtain optimum condition as follows:pressure 20 MPa,temperature 40℃,time 2 h.Meanwhile,in order to get high quality H.rhamnoides oil with lower free fatty acid content,two-step separation method was used:the first step at pressure 12 MPa and temperature 40℃;the second step at pressure 6 MPa and temperature 28℃.Analysis and comparison of physical properties of H.rhamnoides oil showed that the two-step separation method is a good method and can be used industrially.