To obtain a higher yield and high quality of peony seed oil, unshelled peony seeds were pretreated with high-temperature alkaline liquor cooking and steam explosion, and the parameters were also optimized. The results were as follows. Firstly, peony seeds were subjected to cook at 105 ℃ for 40 min in an alkaline liquor with the concentration of sodium bicarbonate being 0.05 mol/L, and the material-liquid ratio (g/mL) was 1∶5. Then the precooked peony seeds were further processed by steam explosion with a pressure of 0.3 MPa, holding for 30 s. After pretreating, the enzymolysis efficiency of peony seed powder by using amylase and glucoamylase was significantly improved, which were more favorable to the release of peony seed oil, and with an oil yield of being 82.07%. Peony seed oil extracted by this method had high quality and nutrition, which meet the first-level indexes of peony seed oil (LS/T 3242—2014) reported in the grain association standard of the People's Republic of China.