AbstractBackground Idiopathic membranous nephropathy (IMN) is the leading cause of nephrotic syndrome in the elderly. The treatment of idiopathic membranous nephropathy is quite challenging due to the particularity of elderly patients. This study intends to investigate the clinicopathological characteristics and initial therapeutic effect of idiopathic membranous nephropathy among elderly patients.Methods A retrospective study of 67 elderly patients (58.2% male, median age 69.0 years, range, 65–83 years) with biopsy-proven membranous nephropathy was conducted at Guangdong Provincial People’s Hospital from 2016 to 2020. Data on clinicopathological characteristics and initial therapeutic effects were analyzed.Results Of the 67 patients, the mean eGFR of overall patients was 66.49 mL/min/1.73m2 while the median urine protein-to-creatinine ratio (uPCR) and urine albumin-to-creatinine ratio (uACR) was 5676.73 mg/g and 2951.56 mg/g, respectively. Pathological data revealed that the membranous Churg’s stage II was the most frequent (71.64%). Moreover, glomerular PLA2R antigen fluorescence intensity of (+) and IgG4 antigen fluorescence intensity of (++) were detected in 63.6% and 86.4% of all patients, respectively. Overall, 44 patients, accounting for 65.7%, achieved remission including complete remission and partial remission within 1 year after renal biopsy. Compared with a non-remission group, the levels of uPCR (6274.6 vs. 3235.6 mg/g, p = 0.007) and uACR (3433.6 vs. 1773.2 mg/g, p = 0.017) were significantly higher in remission group. The proportion of immunosuppressive therapy in the remission group was also higher (86.4% vs. 30.4%, p