Abstract: Gap junction plays a significant role in intercellular direct communication. Connexin 43 （CX43），the major protein in the intercellular gap junction, has specific expression in uterine myometrium. It can regulate the signaling pathway of myometrial smooth muscle cell，thereby affect the coordination of uterine contraction. The paper indicates the relationship between CX43 protein and gap junction, the role of CX43 in the expression in myometrial smooth muscle cell and how phosphorylation events regulate the signaling pathways in it， and how CX43 protein affect the coordination and contraction of uterine，then provides the theory support for the prevention of premature birth and postpartum hemorrhage caused by uterine inertia.

Key words: Connexin 43, Gap junction, Myometrium, Myocytes, Smooth muscle, Extracellular space