The dalargin influence on the blood system erythroid link of the stressed animals with the hypothyroidism is studied by the authors of the article. It is known that hypothyroidism leads to the strengthened destruction of erythrocytes and to their reserve exhaustion in the bone marrow. The stress in hypothyroidism conditions reduces the erythrocyte destruction, stimulates the heteroblastic erythropoiesis and prevents the erythron exhaustion. The dalargin introduction increases the erythrocyte safety even more, activates homoblastic erythropoies is and completely normalizes the erythrocyte number and structure in the peripheral blood.