AgNORs (argyrophilic proteins associated nucleolar organizer regions) has been used to identify whether the cells are malignant or not in the cancer research. It was studied by means of morphometerology, in this report, that changes of AgNORs counting and some morphometric parameters of human embryo lung cell line (HEL-9402) appeared significantly after the HEL-9402 was irradiated by ,60,Co γ-ray. The change character of AgNORs number showed a tendency of increasing gradually with increase of irradiation doses. The implication of changes of AgNORs' area, perimeter and equivalent diameter is not sure although they changed obviously, because they were influenced by the changes of cell nuclei. In conclusion, AgNORs counting may be used to study the relationship between effects and doses during cell neoplastic transformation induced by radiation and expected to become a parameter of identifying malignant degree of transformed cells.