Abstract: The outbreak of shrimp “glass post-larval disease” has led to a large number of diseases of shrimp larvae, bringing huge losses to aquaculture. Using the recently identified Vibrio parahaemolyticus vp-HL of the “glass post-larval disease” pathogen Vibrio parahaemolyticus, the antagonistic antibacterial screening of Bacillus of marine origin was carried out to obtain a strain of Bacillus velezensis MCCC 1A15695 that can effectively inhibit the strains MCCC 1A15695. After isolation and activity determination, the effective bacteriostatic substances were proteins, with a wide inhibitory spectrum, and had inhibitory effects on 17 pathogenic microorganisms, including a variety of Vibrio pathogens. After Q Seharose Fast Flow anion column chromatography, polyacrylamide gel electrophoresis (SDS-PAGE) and liquid chromatography-mass spectrometry (LC-MS), the effective bacteriostatic substances in the active protein components were subtilisin, hypothetical protein and Alpha-amylase. In view of the high biosafety of proteins, the results provide a theoretical basis for the subsequent development and utilization of probiotics.