Common carp is a lower additional value fish that exists in large amount in China. This study investigates nutritional and digestive properties of protein from carp extracted by pH shifting methods. According to the obtained data in this study, pH shifting method is a good protein recovery method that can effectively remove bone spurs, skin, fat and other impurities. In addition, sarcoplasmic proteins can also be recovered. The nutritional properties of protein isolates of carp were suitable for supplementing as an ingredient for human consumption. The pH-shift process greatly improves the protein digestibility. Therefore, there are broad application prospects of the protein isolation as protein ingredients in food industry.