Abstract: The effects of composite biological preservative containing 10% NaCl, 3% ethanol, 2% chitin, 5% glycerol, 3% sucrose and 10% antifreeze proteins (AFPs) on storage quality of yesso scallop, Patinopecten yessoensis, were investigated by sensory evaluation, total volatile base nitrogen (TVB-N), total bacterial count (TVC), pH, hardness, springiness, cohesiveness, chewiness, SH- count and soluble proteins during storage in (-20±2)℃. Results showed that the biological preservative led to inhibit effectively increase in TVB-N level and decline of sensory evaluation and hardness, but almost did not affect the change in TVC, pH, springiness, cohesiveness chewiness, SH- count and soluble protein level. It is concluded that the storage quality is improved and shelf life is prolonged in the scallop treated with the biological preservative.