Objective To observe the initial mechanism investigation in immune escaping correlated T cell proportion of Lewis lung cancer by Fuzheng-Peiyuan formula. To provide a theoretical basis for the application of the Chinese medicine of strengthening the body resistance in clinics. Methods The healthy C57BL/6J mice were divided into six groups by the random number table: the Chinese medicine group, the Chinese medicine plus chemotherapy group, the chemotherapy group, the model group and the normal control group. There were 6 mice in each group. All the groups expect the normal control group were inoculated subcutaneously with Lewis lung cancer cell suspension 0.2 ml. The medicine given to the Chinese medicine group were orally Fuzheng-Peiyuan formula with 8.17 g/kg. The combination group was given intraperitoneal injection of cyclophosphamide 60 mg/kg and orally Fuzheng-Peiyuan formula 8.17 g/kg. The chemotherapy group received the injection of cyclophosphamide 60 mg/kg and intragastric administration of normal saline. The model group and normal control group were administered with saline. After continuous administration for 13 days, the expressions of CD4, Foxp3, CD8 and CD28 in spleen cells of tumor bearing mice were observed by flow cytometry. Results Compared with the model group, the chemotherapy group and the chemotherapy combined with Chinese traditional medicine group showed that tumor weight (1.76 ± 0.42 g, 1.40 ± 0.43 g vs. 4.37 ± 0.59 g) significantly decreased (P<0.01); and the CD4+ Foxp3+ cells of mouse spleen cells in the Chinese medicine group and Chinese medicine plus chemotherapy group (11.25% ± 1.69%, 9.30% ± 2.68% vs. 14.21% ± 1.50 %) significantly decreased (P<0.05 or P<0.01). Conclusions The result initial proved that the Chinese medicine could strengthen the body resistance, adjust the proportion of Treg and CTL in spleen T cell in tumor-bearing mouse.