The method of water bath oscillation assisted with ethanol extraction was used to optimize the extraction process of polyphenols from Malus asiatica Nakai, and the composition of polyphenols was analyzed. The optimal extraction conditions of unripe M. asiatica were the volume fraction of ethanol 50%, solid-liquid ratio of 1∶25(g∶mL), water bath oscillation time with 50 min, and water bath oscillation temperature of 30 ℃ via the orthogonal experiment. Under these conditions, the polyphenol yield could reach(7.875±0.008) mg/g. Similarly, the optimal extraction conditions of ripe M. asiatica were the volume fraction of ethanol 60%, solid-liquid ratio of 1∶25(g∶mL), water bath oscillation time with 30 min, and water bath oscillation temperature at 40 ℃, correspondingly, the polyphenol yield could reach(10.259±0.020) mg/g. The results of liquid chromatography showed that there were four kinds of polyphenols in the unripe M. asiatica, including chlorogenic acid(22.03%), proanthocyanidin B2(8.875%), epicatechin(5.95%), and phloperidin(1.259%). These four kinds of polyphenols accounted for 38.117% of the total polyphenols. Meanwhile, the above four kinds of polyphenols in the ripe M.asiatica were 41.075%, 5.641 3%, 8.325 2%, and 0.499 8%, respectively. In addition, (+)-catechtin was also found with the fraction of 7.244 4%, and the above five kinds of polyphenols accounted for 62.786 5% of the toal polyphenols in the ripe M. asiatica. However most unknow polyphenols were not detected in the ripe M. asiatica. The ripe fruit had more polyphenol and nutrition than that in the unripe one.