In ordinary settings, human immunodeficiency virus (HIV)-associated nephropathy should be considered when HIV infection is associated with heavy proteinuria. On the other hand, hepatitis B virus (HBV) may also play a role in the development of glomerular injury among patients with HIV infection, since HIV and HBV infections commonly occur together due to shared modes of transmission. We present here a case of nephrotic syndrome in an HIV-positive patient complicated with HBV infection. A renal biopsy revealed sparse granular deposits of immunoglobulin G in the subepithelial region, consistent with membranous nephropathy (MN) stage I. Moreover, immunostaining exhibited weak anti-hepatitis B core activity within glomeruli. These results led us to consider that HBV-associated MN might play a role in the development of nephrotic syndrome. Although anti-viral treatment for patients with HBV-associated MN has been suggested to be clinically effective, the use of two anti-HIV agents (tenofovir and emtricitabine), both of which have anti-HBV activities, was not effective for the patient's nephrotic syndrome, despite obtaining a decrease in the serum HBV-DNA levels. A lack of prospective data suggests that many decisions on the treatment of glomerulopathies with HIV infections are potentially empirical. Obviously, further studies and accumulated clinical experience are required to better determine the pathogenesis and management of HBV-associated MN among patients with HIV infections.