Bioengineered　marine　microalgae　Schizochytrium　sp.　is　currently　used　to　produce　docosahexaenoic　acid　(DHA).　However,　following　DHA　extraction,　the　remaining　protein-rich　materials　are　not　well　utilized.　In　this　study,　we　report　that　marine　microalgae　bioengineered　Schizochytrium　sp.　hydrolysate　(MESH),　which　exhibits　a　unique　peptide　profile　as　identified　by　Ultra　Performance　Liquid　Chromatography　coupled　with　Q-TOF　mass　spectrometry(UPLC/Q-TOF-MS),　ameliorated　bowel　inflammation　in　mice.　In　a　mouse　model　of　experimentalcolitis　induced　by　dextran　sulfate　sodium,　compared　with　the　control　mice,　the　mice　treated　with　MESH　were　highly　resistant　to　colitis,　as　demonstrated　by　marked　reductions　in　body　weight　loss,　clinical　colitis　scores,　colonic　histological　damage,　and　colonic　inflammation.　Mechanistically,　MESH　attenuated　the　induction　of　pro-inflammatory　cytokines　and　increased　the　induction　of　anti-inflammatory　cytokines.　MESH　also　promoted　the　proliferation　of　colonic　crypt　stem　cells　and　progenitor　cells　required　for　crypt　repair.　Collectively,　these　results　reveal　a　previously　unrecognized　role　of　MESH　as　a　potential　anti-inflammatory　treatment　for　colitis.