Membranous nephropathy (MN) is an autoimmune kidney disease with the clinical hallmark of causing high level proteinuria. MN is caused by circulating antibodies binding to targeting antigens on the surface of podocytes – specialized endothelial cells contributing to the formation of the glomerular filtration barrier. Histomorphologically MN is characterized by a deposition of IgG along the glomerular basement membrane (GBM) – predominantly IgG4 in primary MN – as well as an accumulation of the respective target antigen, thickening of the GBM and effacement of podocyte foot processes. The predominant MN target antigen in 70-80% of MN patients is the phospholipase A2 receptor 1. Additional target antigens, which occur with lower frequencies, have recently been described. The aim of the study was the identification of a novel MN target antigen, which fulfills the typical criteria of MN target antigen: being a podocytic membrane protein, which is recognized by IgG4 subclass specific autoantibodies. Performing a mass spectrometry analysis based on a TMT-based relative quantification approach of immunoprecipitated samples resulted in the identification of Netrin G1 (NTNG1) as a novel MN target antigen. The results were validated using immunohistochemistry, Western Blot and ELISA. The molecular characterization of patients with MN will allow a better diagnosis and clinical management of these patients in the future.