The paper concerns three-dimensional study of the organization of the subepicardial network of the blood and lymphatic microvessels of the heart with the aid of scanning electron microscopy of the injected replicas. It is established that the arterioles have regular orientation of the imprints of the nucleus-containing zone of endotheliocytes. The capillaries belonging to the subepicardial network form a thick mesh and are strictly oriented along the muscular bundles. There is no characteristic relief on the surface of the capillaries. The study of the relief of the post-capillary venules made it possible to record different orientation of the imprints of the nuclei-containing zones of endotheliocytes on their surface. The study of structure of "leaks" formed as a result of leaking of resin from the venular segments of the bed enabled one to elicit their passage into the lymphatic capillaries. The latter are represented by flattened tubes, placed over the blood vessels.