Factor FXIII (FXIII) is a plasma transglutaminase that catalyzes the cross link formation between fibrin chains to stabilize the clot. Beside it s function in hemostasis FXIII has a role in wound healing and embryo implantation--processes that involve angiogenesis. In this review we discuss the role of FXIII in angiogenesis and the molecular mechanisms underlying its pro-angiogenic effect. In addition, FXIII role in wound repair is discussed.