Objective To study the preparation and the structure identification of peptides from hydrolyzates of oyster. Methods The oyster protein was hydrolyzed with trypsin. The hydrolysates were purified using Sephadex G25 gel chromatography,DEAE-Sepharose FF ion exchange chromatography,reversed-phase HPLC on C18 column. Results The peptide F32 was finally isolated from the oyster hydrolysates.The oyster protein was hydrolyzed with trypsin. IR spectrum showed the conformation of peptide chain was ?-helix.the amino acid sequence of F32 was determined by ESI-MS/MS. The sequence of F32 was as follows:Arg-Gln-Ile or Leu-Gly-Ala-Thr-Asn-Ala. Conclusion The research result would provide foundation for the structure-activity research of the peptide F32.