Objective: The sequence characteristics and gene expression pattern of CsrA， an important post-transcriptional regulatory protein， in Shewanella putrefaciens from aquatic products were investigated in this study. Method: The csrA gene of S. putrefaciens was cloned， and the structural characteristics and interaction protein network of CsrA were analyzed by bioinformatics methods. Moreover， the expression characteristics of csrA gene in response to cold， heat， high salt， starvation， ethanol and quorum sensing signal molecules were analyzed by real-time PCR. Results: CsrA is a highly conserved hydrophilic protein with nine phosphorylation sites， consisting of two α-helixes and five β-sheet， and active structure exists as a dimer. CsrA was predicted to interact with proteins that involved in protein synthesis， flagellar assembly and movement， biofilm formation， and quorum sensing regulation. In addition， csrA gene expression was significantly induced at 4 ℃ for 5 h， while immediately induced at 45 ℃ for 1 h. High salt concentration significantly induced csrA gene expression. The expression of csrA gene increased gradually in nutrient deficiency medium， which was significantly higher than that in the control group at 5 h. The expression of csrA gene was continuously up-regulated in the 5% ethanol group， while 10% ethanol reduced the expression of csrA. Quorum-sensing signal molecules induced the up-regulated expression of csrA gene. Therefore， CsrA is closely related to the spoilage caused by S. putrefaciens and plays an important role in its response to different environmental conditions， which can provide reference for further analysis of the biological function of CsrA.