Objective:To explore the inhibitory effects of Jianpi Jiedu Recipe on the transplanted tumor in tumor bearing mice with syndrome of spleen deficiency and the regulatory effects on the intestinal flora in mice with syndrome of spleen deficiency,and discuss the relationship between the two. Methods36 mice from total 48 mice were randomly taken and the mice model of spleen deficiency was established by water decoction of senna. The remaining 12 mice were taken as the normal saline(N.S.)group. Then the model of transplanted tumor was established by CT 26 cells. The 36 model mice of spleen deficiency were randomly divided into the spleen deficiency group and Jianpi Jiedu Recipe(JPJD)groups with low-and high-dose,12 mice in each group. After intragastric administration for continuous 4 weeks,the mice in each group were sacrificed. The tumor was weighed and the inhibition rate was calculated. The thymus index and spleen index were calculated. The proportion of CD4,+, and CD8,+,Tcells was detected by flow cytometry. The serum level of IL-17 was detected by ELISA. The diversity of intestinal flora was determined by 16S rRNA gene sequencing.  Results:The average tumor weight and the serum level of IL-17 in the spleen deficiency group were higher than those in the N.S. group and JPJD groups with low-and high-dose,and the thymus index and spleen index,the proportion of CD4,+, T cells in peripheral blood and CD4,+,/CD8,+, ratio in the spleen deficiency group were lower than those in the N.S. group and JPJD groups with low-and high-dose,with statistically significant differences(P,<,0.01). Also,bacteroides was significantly increased and firmicutes was significantly decreased in the intestinal flora of mice in the spleen deficiency group,which showed the obvious dysbacteria. Compared with the N.S. group and JPJD groups with low-and high-dose,bifidobacteria and lactobacillus were decreased and enterobacteria and enterococcus were increased in the spleen deficiency group.  Conclusion:Jianpi Jiedu Recipe can inhibit the growth of subcutaneous tumor in tumor bearing mice with syndrome of spleen deficiency,increase the ratio of CD4,+,/CD8,+, and decrease the secretion of IL-17. These effects may be associated with the improvement on alteration of intestinal flora in mice with spleen deficiency.