Microbial activity is by far the major factor affecting the quality of fresh aquatic product. Shewanella baltica is widely known to be responsible for specific spoilage organisms (SSO) in refrigerated marine fish, due to the high amine metabolism, the strong proteolytic ability and biofilm forming ability respectively. This specific spoilage bacteria could encounter a series of stresses in the various unfavorable environmental condition during the processing and storage of food, which is closely related to the bacteria stress response factor Sigma. The differences in gene transcription levels and related metabolic pathways in RpoN mutant of S.baltica were analyzed. The research will provide a new theoretical basis for revealing the mechanism of food microbial spoilage, and lays a solid foundation for the healthy development of the aquatic industry.