The placenta plays a major role in the development of blood cells in the mouse and human embryo. Hematopoiesis and vasculogenesis in placenta are two closely interconnected processes. The mouse model has been widely used to study placental hematopoiesis. During mid-gestation, mouse placenta generate blood cells and support the proliferation, maturation and erythroid differentiation of hematopoietic cells within two major vascular niches in the labyrinth. Here, we review the vasculogenesis in chorioallantoic mouse placenta and the current knowledge on hematopoietic activity, niche and origin in mice placenta.