In our work, we conducted studies to evaluate the reconstruction of an artificially created critical radial defect in rats with the use of tri-calcium phosphate scaffold enriched with erythropoietin (ЕРО). A model of the bone defect on the radius forearm in rats of a critical size has been developed. This model allows to conduct the study without the use of osteosynthesis. EPO is a well-known hormone which regulates formation of the red blood cells (2, 3). ЕРО increases the expression of VEGF and promotes angiogenesis (3, 4). Therefore, EPO may have a great potential for use as a growth factor for angiogenesis and play its particular role in the bone tissue regeneration. There are no published studies that describe interactions between EPO and biomaterials for development of the bone tissue. Thus, the purpose of this study was to evaluate the interaction between EPO and tri-calcium phosphate scaffold (TCP) with a well-studied biocompatibility and the given porosity, as well as to determine whether EPO in the enriched TCP will promote the bone regeneration. The X-ray analysis was performed in 10 days, 28 days and 3 months after the surgery. The histological analysis was performed in 28 days and 3 months after the surgery. The results have demonstrated that the complex of TCP scaffold with erythropoietin is a promising growth factor for stimulating the development of the bone tissue, since the TCP scaffold enriched with erythropoietin is very easy to obtain in a noninvasive and simple procedure, as well as the complex promotes interaction with the surrounding tissues and induces the bone regeneration.