Abstract Background and Aims Membranous nephropathy (MN) is the most prevalent cause of nephrotic syndrome in adult population. Our aim was to assess long term renal outcome of primary membranous nephropathy patients. Method In this retrospective study adult patients with biopsy proven membranous nephropathy from 2000 till 2015 with follow up of at least 5 years from UHC Zagreb were included. Extensive clinical workup was done to exclude patients with secondary MN. Except otherwise stated, data are shown as N (%) or median with interquartile range (IQR) and accompanied p levels. Results Between 2000 and 2015, 48 patients were diagnosed to have idiopathic/primary membranous nephropathy, out of which 33 (68%) MN patients had follow up of at least 5 years and where further analyzed. They were predominantly male 20 (60.6%) of average age of 52 years (min – max 19 - 76). High risk MN patient 25 (75%) were treated with immunosuppressive therapy, dominantly with cyclophosphamide and corticosteroids. During the median follow up of 10 (7 – 14) years, 19 (57%) accomplished complete remission and 11 (33%) partial remission. One (3%) patient did not achieve remission and 2 (6.1%) were in relapse of nephrotic syndrome at last follow up. Proteinuria significantly decreased (6.2 (3.3 – 10.9) vs. 0.2 (0.14 – 0,90); p < 0.001) and there was no significant change in creatinine level (87 (42.8 – 101.5) vs. 93 (68.5 – 140.5; p = 0.332)). In follow up there were 5 (15%) carcinomas detected; one of each origin (colon, pancreas, lung, prostate, lymph nodes) approximately 7,8 years after the diagnose of MN. Limitation of this study could be selection bias but there was no difference in renal function at presentation of all MN patients and those who had at least 5 years follow up. Conclusion Renal long-term outcome of patients with idiopathic MN in our cohort was excellent. Nevertheless, there is high prevalence of cancer and therefore regular screening for cancer disease should take place in this population of patients. Also, drugs with cancerogenic potential should be avoided, as well as bear in mind cumulative dose of drugs applied.