Abstract: Implantation is a procedure that establishes links of tissues and physiology gradually between activated blastocyst trophoblast and receivable endometrial epithelial cells. In equids， the procedure involves two distinct types of trophoblast: a minor invasive trophoblast girdle (endometrial cups) and a major non-invasive allantochorion (microcotyledonary epitheliochorial placenta). Therefore, equine is a kind of mammals that provide the opportunity to do research about both invasive and non-invasive trophoblast tissue together. A lot of molecules are involved in the procedure of implantation. Advance of researches on the characters， procedure and molecular mechanism of implantation in the mare has been reviewed， and it’s useful to reduce the incidence of early pregnancy loss and abortion of mares.

Key words: mare; implantation; molecular regulation