Objective To isolate and screen lactic acid bacteria from the intestinal tract of marine fish with inhibitory activity against Vibrio parahaemolyticus and to investigate their antibacterial activity.Methods Using V. parahaemolyticus as the indicator bacterium, preliminary antibacterial screening was performed. The strain was identified through morphological, physiological, and biochemical characteristics as well as 16S rRNA gene sequence analysis. The antibacterial spectrum of the strain was determined, and the antibacterial stability, antibacterial mechanisms, and minimum inhibitory concentration (MIC) of its cell-free supernatant (CFS) were analyzed.Results A strain, Y10-1, showing strong antagonistic activity against V. parahaemolyticus was screened and identified as Weissella confusa. The antibacterial substances produced by this strain demonstrated broad-spectrum antibacterial activity, were heat resistant (100 ℃ for 15 min), and exhibits inhibitory activity against V. parahaemolyticus within a pH range of 2.0~9.0. The MIC against V. parahaemolyticus was 5%. Under the condition of 3×MIC, the antagonistic effect against V. parahaemolyticus was the most pronounced.Conclusion The strain Y10-1 screened in this study exhibits good antagonistic activity against V. parahaemolyticus and has considerable potential for development and application in food preservation.