Objective To investigate the curative effect of Bifidobacterium Triple Viable Bacteria Enteric-Coated Capsules in the treatment of children with acute leukemia chemotherapy-related diarrhea in order to guide clinical medication. Methods Fifty children with chemotherapy-related diarrhea associated with acute leukemia who were initially treated in the Children's Hematology Ward of the Hematology Diagnosis and Treatment Center of Tai'an Central Hospital Affiliated to Qingdao University from March 2017 to March 2021 were selected as the research subjects.According to the random number table method, they were divided into the experimental group and the control group, with 25 cases in each group.Both groups were given symptomatic and supportive treatment such as intravenous infusion,while the experimental group was added with oral administration of Bifidobacterium Triple Viable Enteric-Coated Capsules, 1 capsule each time, 2-3 times per day, for a total of 2 weeks of treatment.The time of diarrhea, the colony counts of Bifidobacterium, Lactobacillus acidophilus, and Escherichia coli in feces, plasma endotoxin and D-lactic acid content, and fecal calprotectin levels were compared between the two groups before treatment and after 2 weeks of treatment. Results The diarrhea time of the children in the experimental group was shorter than that in the control group, and the difference was statistically significant (P＜0.05).The colony counts of Bifidobacterium and Lactobacillus acidophilus in feces 2 weeks of treatment in the experimental group were more than those of the control group,the differences were statistically significant (P ＜0.05).The number of Escherichia coli colonies in the feces of the children in the experimental group was less than that in the control group after 2 weeks of treatment, the difference was statistically significant (P＜0.05).The children in the experimental group were treated for 2 weeks, the levels of plasma endotoxin, D-lactic acid, and fecal calprotectin were lower than those in the control group, and the differences were statistically significant (P＜0.05). Conclusion Bifidobacterium Triple Viable Enteric-Coated Capsules can shorten the time of chemotherapy-related diarrhea in children with acute leukemia, regulate the balance of intestinal flora, and improve the intestinal mucosal barrier function, which is worthy of clinical promotion.