BACKGROUND: Tumor occurrence and growth are highly correlated with the degree of inflammation and immunological activity. Reducing the level of inflammation in tumor-bearing body to relieve immune suppression and enhance anti-tumor immune function has become an important strategy for tumor treatment. OBJECTIVE: To investigate the effect of albumin-bound paclitaxel combined with Sophora subprostrate polysaccharide (SSP) on inhibiting inflammation, reducing immunosuppression, enhancing anti-tumor immune function and slowing the progression of tumor in tumor-bearing rats, and to provide certain scientific basis for the clinical application of combined drugs in tumor. METHODS: The rats were put into three groups at random: normal control, model group, and drug treatment group. After the end of drug intervention, the tumor was taken out and weighed to observe the tumor growth of the rats. Tumor necrosis factor (TNF-α), interleukin (IL) 1β, IL-10, perforin, and granzyme B were found by Western blot in the local tumor tissues of experimental rats. The protein expression levels of Arginase-1 (Arg-1) and Cyclooxygenase 2 (COX-2) were determined. HE staining was used to observe the inflammatory infiltration of the tumor. Using flow cytometry, the proportions of anti-tumor immune cells-CD8 + T cells, NK cells, and immunosuppressive cells-in local tumor tissues were evaluated. In addition, spleen T cells isolated from normal rats were co-cultured with spleen myeloid derived suppressor cells (MDSC) from tumor-bearing rats in the model group and the combined treatment group. Cell Trace Far Red was used to identify T cell proliferation, flow cytometry was used to determine the level of T cell activation from CD25 expression, and in vivo immunosuppression in tumor-bearing rats was examined. RESULTS: The combined therapy group experienced a considerable decrease in tumor weight as compared to the model group. TNF-α and IL-1p levels in the vicinity of the tumor tissues reduced following intervention, although IL-10 levels, which are anti-inflammatory cytokines, did not significantly change. The results of the HE staining revealed that the intervention group's tumor had less inflammatory infiltration than the model group did. After intervention, the percentages of CD8 + T cells and NK cells in local tumor tissues increased. Additionally, the intervention group's levels of protein expression for perforin and granzyme B were considerably higher than those of the model group. In the nearby tumor tissues, there were lots of MDSC. Following the intervention, the proportion of MDSC in the local tumor tissues was significantly reduced, and the expansion of MDSC was reduced. Additionally, the intervention group's COX-2 and Arg-1 protein expression levels in the tumor-specific tissues were significantly lower than those of the model group. The outcomes of in vitro co-culture demonstrated that rats in the combination group had higher levels of T cell proliferation and activation than animals in the model group. CONCLUSIONS: Albumin-bound paclitaxel combined with Sophora subprostrate polysaccharide can reduce the local inflammation level, promote the proportion of CDB + T cells and NK cells and cell killing function, reduce the proportion of MDSC and immunosuppressive level, enhance the anti-tumor immune function of tumor-bearing mice, and slow the growth of tumors.