Abstract: Objective To compare the absolute counts of lymphocyte subsets in patients with chronic kidney disease(CKD)3~5,examine the risk factors related to lymphocyte subsets and elucidate the relationship between renal function and immune homeostasis. Methods A total of 130 non-dialysis patients with CKD3~5 were assigned into two groups of CKD3~4(n=44)and end-stage renal disease (ESRD,n=86). Basic clinical markers and lymphocyte subsets were compared between two groups. The correlations between lymphocyte subsets and clinical parameters were analyzed and influencing factors of lymphocyte subsets examined. Absolute counts of lymphocyte subsets were compared between young and middle-aged patients with CKD3~5 after propensity score matching. Results The levels of neutrophil-to-lymphocyte(NLR),creatinine,urea nitrogen,parathyroid hormone(PTH),blood phosphorus,β2-macroglobulin(β2-MG)and α -macroglobulin(α -MG)were higher in ESRD group than those in CKD3~4 group(P<0. 001)while the levels of hemoglobin and calcium were lower(P< 0. 001). Absolute counts of CD3⁺,CD4⁺,CD8⁺T lymphocytes,B cells and NK cells were lower in ESRD group than those in CKD3~4 group(P<0. 01). However,no significant inter-group difference existed in the ratio of CD4⁺/CD8⁺(P>0. 05). Estimated glomerular filtration rate(eGFR)was correlated positively with CD3⁺,CD4⁺,CD8⁺T lymphocytes,B cells and NK cells(P<0. 001)but negatively with NLR(P<0. 001). β2-MG was an independent risk factor of CD3⁺,CD4⁺ lymphocytes and B cells levels. Age was an independent risk factor for the levels of CD3⁺,CD8⁺T lymphocytes and B cells. Compared with young CKD3~5 patients,absolute counts of CD3⁺,CD8⁺T lymphocytes and B cells declined markedly(P<0. 05)while ratio of CD4⁺/CD8⁺ rose(P<0. 01)in middle-aged patients. Conclusion Deterioration of renal function is closely correlated with a decline of lymphocyte subsets. Both age and β2-MG are important influencing factors of immune dysfunction in CKD3~5 patients.