The hemp oil was extracted from the hemp kernels by gradient supercritical carbon dioxide and analyzed using national standard method. The result showed that the fatty acid compositions of hemp oil were different at every stage when using three-step gradient supercritical carbon dioxide. As the extraction pressure and temperature rised, certain trace fatty acids were extracted , namely C20:3n6, C22:0, and C24:0. The tocopherol isomer of hemp oil was mainly -β+γ-- tocopherol. Tocopherol was concentrated by the former two extraction step during the three-step gradient supercritical carbon dioxide extraction