Objective: To observe the relationship between serum aPLA2Rab titer and the severity of renal disease and renal prognosis in patients with PLA2R-related membranous nephropathy. Methods: Patients with PLA2R-related membranous nephropathy confirmed by renal biopsy in the Department of Nephrology of the First Affiliated Hospital of Soochow University were included and were followed up for ≥1 year. The end point was renal insufficiency, defined as a 40% decrease of eGFR from baseline. Results: A total of 273 patients were included in this study, of which serum aPLA2Rab titer <50RU/ml group (low titer group) had 44 cases, 50-150RU/ml group (medium titer group) 142 cases and >150RU/ml group (high titer group) 87 cases. Serum aPLA2Rab titers were significantly correlated with gender, baseline serum albumin, serum creatinine, total cholesterol, urinary NAG, urinary RBP, and glomerular C4 deposition. Multivariate Cox analysis showed that aPLA2Rab titer was still an independent risk factor for renal insufficiency after correction for clinicopathological parameters. The cutoff point of serum aPLA2Rab titers for predicting renal insufficiency was 135.66RU/ml, with a sensitivity of 65.8% and a specificity of 63.8%. The renal survival rates without reaching renal insufficiency at 1 year, 5 years and 10 years were all 100% in the low titer group; 100%, 87.0% and 75.5% in the medium titer group; 95.4%, 72.3% and 72.3% in the high titer group respectively; there was a significant difference among the three groups. Conclusion: This study further confirmed that the serum aPLA2Rab titer level in patients with PLA2R-related membranous nephropathy was related to disease severity and renal prognosis, providing theoretical support for the new concept of immunological remission as the therapeutic target.