The relationship between radiation doses and its biological effects in lymphocytes was used as one of the most sensitve methods in early clinic work. The investigation of the change of activity, mortality, chromosome aberration, rosette formation, cell membrane and DNA molecule in lymphocytes was performed in different laboratories.,Lymphocyte subpopulation was induced by PHA, ConA, PWM and LPS respectively. The radiation effects on the transformation in the subpopulation was studied. More research work in T-lymphocytes stimulated by PHA has been done. In our laboratory it demonstrated that PWM-induced and ConA-induced lymphocytes was more sensitive to radiatiation, both of them decreased the effects of help B lymphocytes transformation. PHA-induced lymphocytes was less sensitive. While the effect of radiation on LPS-induced Lymphocytes was not very obvious,The study of lymphocyte subpopulation and the radiation effect on it by using monoclonal antibody technique is to be carried out, then the effect of radiation on the main chains in immunity would be illustrated.,Study of radiosensitivity of lymphocytes in various patients is beneficial to understanding defects in immunity and helpful of in design of more effective radiation regimes in some leukemia patients.