Abstract: Glucocorticoid-induced tumor necrosis factor receptor (GITR) is an important functional molecular of regulatory T cells (regulatory T cells，Tregs) expressed in thymus and peripheral lymphoid organs. Numerous studies have shown the key role of GITR in differentiation and extension of Tregs. Furdermore，GITR is an effective marker of Tregs and play an important role in immune regulation. GITR has many important biological activities，including cell proliferation，differentiation，survival and apoptosis，etc. The interactions of them can break immune tolerance mediated by Tregs，induce or aggravate autoimmune diseases，such as asthma，diabetes，arthritis and systemic lupus erythematosus，etc. All pregnancies comply with the rules of immune tolerance，Tregs play an important role in protecting fetus from immune attack. Many studies have shown that interruption of the interaction in Tregs during the pregnancy can lead to the generation of fetal specific antigen，which in turn will lead to adverse pregnancy outcome. Now a review will be made here on GITR mediated by Tregs in immune tolerance.

Key words: Glucocorticoid-induced TNFR-related protein, Receptors，tumor necrosis factor, T-lymphocytes，regulatory, Immune tolerance, Autoimmunity, Pregnancy