The proliferation and death of hemopoietic cells in the regenerating liver of 17-day outbred albino rat fetuses were studied during 2 days after resection of 20% of the organ. The mitotic index of hemopoietic cells in the resected liver increased significantly 24 h after the operation in comparison with the control fetuses. No increase in the counts of apoptotic hemopoietic cells was detected in the regenerating liver. Hence, resection of 20% of the liver in rat fetuses stimulated the proliferation of hemopoietic cells and did not stimulate their apoptosis.