Taking orange peel which was citrus fruit processing waste as raw material，the total flavonoids yield as index，with ultrasonic assisted extraction，through single factor experiments and orthogonal tests to optimum the extraction technology of total falvonoids from orange peel，in order to obtain optimum process conditions of orange flavonoid by ultrasonic assisted extraction and provide some theoretical guidance for the industrial production of flavonoids from orange peel.The results showed that for ultrasonic assisted extraction，the yield of orange flavonoid reached 96% under extraction conditions of extracting time 30 min，alcohol concentration 60%，solid to liquid ratio 1∶25 mg/L.