Anti-HCVAg positivity is one of the symptoms that confirm the diagnosis of noncryoglobulinemic MPGN (membranoproliferative glomerulonephritis) as well as membranous nephropathy. Hepatitis C virus (HCV) is a single-stranded RNA virus that was first identified in 1989 and is now estimated to affect approximately 100 × 106 people worldwide, mainly through blood product transmission and intravenous drug use. The relationship between HCV infection and glomerular diseases has gradually increased in the last decade, and it is now believed that HCV-related kidney damage mainly includes cryoglobulinemic MPGN, noncryoglobulinemic MPGN, and membranous glomerulopathy (MPGN). membranous nephropathy (MN). The association between HCV and cryoglobulinemia was first reported in 1990, and recent studies have found evidence of HCV infection in 95% of patients with type II cryoglobulinemia and 50% of patients with type III cryoglobulinemia, including the presence of circulating anti-HCV antibodies in serum, polyclonal IgG anti-HCV antibodies in cold precipitates, and HCV-RNA in plasma and cold precipitates. HCV-associated MPGN was first reported in 1994, and HCV-associated proteins were later detected on kidney tissue sections from patients with cold globulinemic MPGN using monoclonal antibodies against specific HCV antigens. The HCV antigen was not detected in 8 HCV-negative patients with cold globulinemic MPGN. It is now believed that cold globulinemic MPGN with HCV is mediated by HCV immune complexes, which are deposited in the subendothelium and mesothelium and activate complement, leading to cell proliferation and inflammatory cell infiltration. However, it is unclear whether HCV antigen mediates glomerular damage independently of cold globulin.