Objective To explore the effects and mechanism of Baitouweng Decoction in intestinal mucosal healing in mice with ulcerative colitis(UC)based on RIPK1/RIPK3/MLKL signaling pathway.Methods Totally 30 C57BL/6 male mice were randomly divided into control group,model group,Baitouweng Decoction group,infliximab group and combination group(Baitouweng Decoction+infliximab),with 6 mice in each group.A mouse model of UC was established by free administration of 3.5%sodium gluconate sulfate solution for 7 days.After modeling,Baitouweng Decoction group was given 8 g/kg Baitouweng Decoction solution by gavage daily,while the infliximab group was given 5 mg/kg infliximab intraperitoneal injection,the combination group was given synchronous gastric and intraperitoneal injection,while the control group and model group were given equal volume of normal saline by gavage for 7 consecutive days.The body mass of mice was recorded daily,fecal characteristics were observed,and disease activity index(DAI)score was performed,colon length was measured after intervention,ELISA was used to detect the contents of serum interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α),RT-qPCR was used to detect mRNA expressions of RIPK1,RIPK3 and MLKL in colon tissue,Western blot and immunofluorescence staining were used to detect the expressions of RIPK1,RIPK3 and MLKL protein in colon tissue.Results Compared with the control group,the model group mice showed a decrease in body mass(P<0.01),an increase in DAI score(P<0.01),a shortened colon length(P<0.01),and an increase in serum IL-6 and TNF-α content(P<0.01);colonic mucosal was destructed,with disappearance of crypts and glandular structures,extensive infiltration of inflammatory cells,and increased pathological score of colon tissue(P<0.01);the mRNA and protein expressions of RIPK1,RIPK3 and MLKL in colon tissue increased(P<0.01,P<0.05).Compared with the model group,the body mass of mice in each treatment group increased(P<0.01),and the DAI score decreased(P<0.01),colon length increased(P<0.01),and the contents of serum IL-6 and TNF-α decreased(P<0.05,P<0.01);the destruction of the colonic mucosal barrier was reduced,the pathological score of colon tissue was reduced(P<0.05);the expressions of RIPK1,RIPK3 and MLKL mRNA and protein in colon tissue decreased(P<0.05,P<0.01).Conclusion Baitouweng Decoction can alleviate intestinal mucosal damage and inflammation in UC mice,and its mechanism may be related to the inhibition of the RIPK1/RIPK3/MLKL signaling pathway.