〔Abstract〕 Objective To analyze the clinical effect of Shenling Baizhu powder in the treatment of diarrhea-type irritable bowel syndrome (IBS-D) of spleen deficiency and dampness excess syndrome. Methods 80 patients with IBS-D of spleen deficiency and dampness excess syndrome treated in Beijing Changping District Hospital from January 2018 to January 2020 were randomly divided into control group and observation group, with 40 cases in each group. The patients in the observation group were treated with shenling baizhu powder and the patients in the control group were treated with simple western medicine. The symptom scores, IBS symptom severity scale (IBS – SSS) scores before and after treatment, and the treatment efficiency of the two groups were compared. Results After treatment, the symptom scores and IBS-SSS scores of the two groups decreased in varying degrees, and the symptom scores and IBS-SSS scores of the observation group were lower than those of the control group (P < 0.05). The total effective rate of the observation group was 95.00%, higher than 75.00% of the control group (P < 0.05). There were no adverse reactions in both groups during treatment. Conclusion The clinical effect of shenling baizhu powder in IBS-D patients with spleen deficiency and dampness excess syndrome is significant. 〔Keywords〕 Diarrhea irritable bowel syndrome; Spleen deficiency and dampness excess syndrome; Shenling baizhu powder