Abstract: Apple（Malus pumila Mill.） peel was extracted with ultrasound assistance using ethanol aqueous solution containing NaOH as extracting solvent, the extraction conditions were optimized by response surface method. The extract was concentrated, and its pH was justified to 3.0 with hydrochloric acid. The mixture was filtrated and filter cake was washed with 10% ethanol aqueous solution. The filter cake was dried, and then degreased by petroleum ether. The residue was crystallized and recrystallized in ethanol to obtain ursolic acid crystal. This method was very simple and easy to scale up, which can make apple peel valuable and can reduce environmental pollution.

Key words: Apple（Malus pumila Mill.） peel, ursolic acid, extraction, separation