Abstract: The extraction methods of phosphatidylinositol from soybean lecithin powder by ionic liquid and ultrasonic wave were studied.The effects of extraction times, solid-liquid ratio, ehanol-BmimOH ratio, extraction temperature, extraction time and ultrasonic power on the purity and extraction ratio of phosphatidylinositol were investigated. The purified phosphatidylinositol products were obtained at the conditions as follows: extraction times 3, solid-liquid ratio 1 ∶ 12, ehanol-BmimOH ratio100∶ 7, extraction temperature 35 ℃, extraction time 15 min and ultrasonic power 360 W.Under these conditions, the purity and extracting yield of phosphatidylinositol were 79.53% ± 3.26% and 68.26% ± 1.15%, respectively.