22.78%和64.14%。Based on the single factor analysis, the effect of liquidsolid ratio, ultrasonic power, extraction temperature, and extraction time on enhancing oil yield from Paeonia suffruticosa Andr. seed was evaluated by response surface analysis. A 4-factor, 3-level Box-Behnken experimental design was applied and the interactions of each factor on the oil yield were also investigated. The optimal conditions were at 54℃ extraction temperature, 11mL/g liquid-solid ratio, 300W ultrasonic power, and 60min extraction time using petroleum ether with a boiling range of 60～90℃ as the extraction agent. Under such conditions, the oil yield is 24.12% after three runs. The extracted oil was analyzed by GC—MS to determine the oil constituents. Unsaturated fatty acids such as linoleic acid and linolenic acid are abundant in Paeonia suffruticosa Andr. seeds. 