The need to improve the knowledge of the processes of blood capillaries and other vessels development is due to the clinical medicine needs in developing more effective methods for treating diseases their outcome depending much on the success of the measures of stimulating the vascular growth and the tissue revascularization (transplantation of organs and tissues, microcirculation disorders, wound healing), or vice versa, the vascular growth suppression (angioma, other tumors, angio-retinopathy in patients with diabetes mellitus, rheumatoid arthritis). The article considers the processes of generation of the endothelium-like cells precursors (angioblasts) from which primitive, then mature capillaries and blood capillary network form in the course of sequential differentiation, migration and association with other endothelial cells. The tissue hypoxia role in the initiation of the processes of vasculo- and angiogenesis and in the germ-cell signal molecules, proteins and other structural components of the extracellular matrix regulation is discussed.