On white non-breeding rats' males (n=60) were determined the experimental chronic intoxication of copper-zinc pyritic ore on rat erythron. The experimental model of chronic intoxication was created on rats by giving them water suspension of ore in a dose of 600 mg/kg of rats' body weight within two months. On the 30-th day of intoxication of copper-zinc pyrite ore there was a decrease in peripheral blood the number of erythrocytes and hemoglobin in 1,2 times compared with the control group (p<0,05). It is established that under the influence of ore the structure of cells of rats' marrow was changed, it was observed reduction of quantity of young cellular forms of erythroidal row. Observed shifts of erythropoiesis are caused by presence of heavy metals in content of ore, which accumulate in small doses in the body, cause the erythropoiesis suppression.