Intestinal　enteritis　is　a　main　issue　in　crucian　carp　production　which　results　in　massive　economic　loss.　Traditional　antibiotics　used　for　disease　prevention　of　crucian　carp　(Carassius　carassius)　have　been　banned,　thus　an　alternative　approach　needs　to　be　identified.　In　this　study,　the　bioactive　peptide　was　evaluated　as　a　diet　supplement　for　preventing　intestinal　inflammation　in　crucian　carp.　Intestinal　inflammation　was　induced　by　intrarectal　administration　of　a　2,4,6-trinitrobenzene　sulfonic　acid　(TNBS)　solution.　The　fish　samples　were　fed　with　different　diets　for　14　days.　The　disease　activity　index　(DAI),　which　included,　fish　swimming,　food　intake,　anal　inflammation,　body　surface,　and　ascites　was　determined　daily.　Intestine　segments　were　stained　with　haematoxylin　and　eosin　(H.E.)　for　histopathological　analysis.　The　expression　of　cytokines,　including　interleukin-1β　(IL-1β),　interleukin-8　(IL-8),　tumor　necrosis　factor　α　(TNF-α),　and　myeloperoxidase　(MPO)　in　crucian　carp　were　determined.　In　TNBS-induced　groups,　the　DAI　scores　were　dramatically　increased　compared　to　the　control　group.　The　histopathological　analysis　showed　that　the　damage　of　the　fish　intestine　after　the　injection　of　TNBS.　The　relative　expression　levels　of　pro-inflammation　cytokines　(TNF-α,　IL-1β,　IL-8,　MPO)　were　significantly　increased　compared　to　the　control　group　on　day　1.　In　the　TNBS-induced　group　feed　with　a　diet　supplemented　with　bioactive　peptide,　the　symptoms　of　intestinal　inflammation　were　relieved　on　day　3　and　the　mRNA　expression　levels　of　pro-inflammation　cytokines　(TNF-α,　IL-1β,　IL-8,　MPO)　were　reduced　compared　to　day　1.　On　day　7,　the　fish　samples　enrofloxacin　group　and　bioactive　peptide　group　were　recovered　from　TNBS-induced　intestinal　inflammation.　This　study　showed　that　the　fish　diet　supplemented　with　bioactive　peptide　could　help　to　prevent　and　recover　from　intestinal　inflammation.　Thus,　the　bioactive　peptide　can　be　used　as　a　replacement　for　antibiotics　to　prevent　disease　in　aquaculture　production.　©　2022