The invention discloses five peptides which can be used as angiotensin converting enzyme inhibitor. The subject invention also discloses a process for the preparation of the products having angiotensin converting enzyme inhibitory activity, which comprises the following steps: (a) adding protein hydrolase to the solution of chicken residues for reaction; (b) separating the chicken residues and liquid after the reaction of step (a) and collecting the separated liquid; and (c) drying the liquid obtained from step (b) to obtain the products.