Abstract: To investigate the immunity of non-IgA mesangial proliferative glomerulonephritis （non-lgA MsPGN）, GIG-immunoglobulin, IL-2 activity and subpopulations of lymphocytes of peripheral blood from 44 cases with non-IgA MsPGN were measured by ELISA and flow cytometry methods. The results were summaried as: 1. The level of GIC-IgM of the patients was higher than that of the controls; 2. GD4 （helper T cell） and the retio of GD4/CD8 were increased in the patients, but the value of CD8（suppressive T cell）was decreased markedly in the patients with non-lgA MsPGN; 3. IL-2 productivity of lymphocytes under the stimulating of PHA was lower than that of controls, but the IL-2 productivity of the patients without nephrotic syndrome was not different from that oI normal controls.