Abstract: Employing defatted yolk power by ethanol-hexane extraction as substrate, yolk peptide with high quality was obtained by hydrolysis with 2.4L Alcalase.The hydrolysis process was conducted for twice and yield rate was up to 41%.The physical and chemical indexes of the product were measured: the peptide content was above 85%and the ash content was less than 10%, which features good solubility and high heat stability within a wide pH range. Activity experiment in vitro indicated that yolk peptide product had strong ability to prevent calcium phosphate from sediment, suggesting a potential on improving intracellular calcium absorption. Meanwhile, the oxidation resistance activity of yolk peptide was conformed in this study.