Abstract: Regulatory T cells (Tregs) possess the function of immune suppression and achieve immunosuppression by the approach of expressing cytotoxic T lymphocyte-associated antigen, perforin-particle enzyme mediated cytotoxic effect, and secretion of cytokines such as IL-10, TGF-β, et al. The antibodies, vaccines and chemical drugs can be applied for targeting FOXP3+CD25+CD4+Tregs, depleting Tregs in peripheral blood and tumor tissues of patients of various forms of cancers. The function of immune suppression can be decreased and antitumor curative effects by immunotherapy can be enhanced.

Key words: Neoplasmas, T-lymphocytes cells, regulatory, Immunotherapy