Myeloid-derived suppressor cells (MDSC) are heterogeneous population of immature myeloid cells, that support tumor growth, by reducing T cell activity. Therefore, drugs which can inhibit MDSC are new predictive immunotherapeutic medicines. We have previously shown that Kampo medicines, Ninjinyoeito (NYT) and Juzentaihoto (JTT), suppress the differentiation of MDSC. In the tumor-bearing state, MDSC migrate to the tumor microenvironment (TME). In the present study, we have investigated the effects of NYT and JTT on the migration to TME. MDSC were isolated from C57BL/6J mice and differentiated into MDSC by the treatment with IL-6 and GM-CSF, after which the migration activity was assessed with transwell assay. The migration of MDSC was stimulated by treatment of 4T1 cancer cells or 4T1-conditioned media, NYT and JTT significantly inhibited the migration. Inaddition, NYT inhibits the phosphorylation of ERK1/2 in MDSC induced by 4T1-conditioned media. Furthermore, NYT considerably suppressed the expression of CCR2 in MDSC. These data indicated that, NYT and JTT suppress not only differentiation, but also the migration of MDSC to TME. This multi-step approach in cancer treatment may be important in the immunomodulatory effects of these Kampo medicines.