Abstract: Objective: To explore the effects of lactadherin on promoting the proliferation of T lymphocyte stimulated by dendritic cells( DCs) and cytokines secretion. Methods: Cord blood monocyte was isolated by density gradient centrifugation，and induced and differentiated into DCs. Culture solution was added into the lactadherin experimental group at day 1 and day 5 after isolation. The mixed culture of mature DCs and allogeneic T lymphocytes were implemented. T lymphocyte proliferation were detected using MTT and CFSE， the levels of cytokines were measured using ELISA. Results: Lactadherin could obviously promote the proliferation of T lymphocyte stimulated by DCs( P ＜ 0. 01) ， the result of coculture of DCs and different proportion T lymphocyte was similar，and the ability of Tlymphocyte proliferation was more significant at day 5 after adding lactadherin( P ＜ 0. 01) . DCs induced by lactadherin could promote the level of T cell secreting a variety of cytokines， the level of interferon- increased significantly at the time of adding lactadherin( P ＜0. 05) . Conclusions: lactadherin can promote the proliferation of T lymphocyte stimulated by DCs to activate adaptive immune response.