To investigate the alterations in the physiological characteristics of Vibrio parahaemolyticus after cold shock， the standard strain ATCC17802 of V. parahaemolyticus was employed as a typical representative to systematically explore the patterns of physiological phenotypic changes under moderate low temperatures of -20， 4， 10， and 15 ℃ for 3， 6， 12， and 24 h， respectively. Through the analysis of sublethal rate， hemolytic activity， swimming motility and biofilm formation ability， combined with the observation of the bacterial morphology via scanning electron microscopy， the impacts of cold shock on V. parahaemolyticus were comprehensively analyzed. The results revealed that the effects of cold shock on V. parahaemolyticus exhibited significant temperature-dependent characteristics： Cold shock above freezing point （4 ℃， 10 ℃， and 15 ℃） promoted biofilm formation through sustained secretion of extracellular proteins， thereby enhancing the environmental adaptability and pathogenic potential of the strain. Conversely， cold shock at -20 ℃ disrupted the cellular structure via ice crystal formation， leading to significantly suppressed bacterial motility， hemolytic activity and biofilm formation.This study provides phenotypic data and a theoretical foundation for the precise risk assessment of V. parahaemolyticus in cold-chain aquatic products and the exploration of cold shock pathways.