Three　Shewanella　sp.　strain　and　three　Pseudomonas　sp.　strains　isolated　and　purified　from　iced　Pseudosciaena　crocea　were　evaluated　in　this　study　for　their　surface　hydrophobicity,　auto-aggregation　ability　and　biofilm　formation　ability　together　with　their　correlation　with　adhesion　characteristics　to　fish　mucus　(gut,　gill　and　surface).　Meanwhile,　the　characteristics　of　biofilm　formation　were　investigated　under　different　conditions.　The　results　showed　that　compared　with　Pseudomonas　sp.,　Shewanella　sp.　had　stronger　surface　hydrophobicity　and　auto-aggregation　ability　and　enhanced　ability　to　adhere　to　fish　mucus　and　form　biofilm.　Principal　component　analysis　(PCA)　and　clustering　analysis　(CA)　showed　an　inter-genus　difference　but　intra-genus　similarity　in　bacterial　adhesion　ability.　Both　the　auto-aggregation　ability　and　biofilm　formation　ability　were　highly　correlated　with　the　adhesion　ability　to　gut　and　gill　mucus,　while　the　surface　mucus　adhesion　ability　was　correlated　exclusively　with　the　biofilm　formation　ability.　In　addition,　biofilm　formation　was　related　to　initial　concentration,　incubation　time,　temperature,　pH,　NaCl　concentration　and　other　environmental　factors.　The　spoilage　bacteria　formed　biofilm　rapidly　from　12　to　24　h　of　culture　and　biofilm　biomass　reached　the　highest　peak　at　36　h,　and　then　gradually　reduced　with　incubation　time.　The　optimum　conditions　for　biofilm　formation　by　Shewanella　were　as　follows:bacterial　suspension　greater　than　106　CFU/mL,　temperature　37,　NaCl　concentration　0.8%　and　pH　7-8.　Biofilm　formation　was　significantly　influenced　by　fish　mucus.　Gill　mucus　promoted　biofilm　formation,　whereas　the　opposite　effect　was　true　for　gut　mucus.　©　2019,　China　Food　Publishing　Company.　All　right　reserved.