We reported a 27-year-old man who developed nephrotic syndrome 12 months after a bone marrow transplantation from his HLA-identical sister for chronic myelocytic leukemia. Anti-nuclear antibodies had been serially investigated after the bone marrow transplantation. They were detected in his serum 5 months before the appearance of proteinuria, but he tested negative at the onset of nephrotic syndrome. Histological analysis of the renal biopsy revealed subepithelial and subendothelial immune deposits in the glomerular basement membrane with increased mesangial matrix and cells. These findings suggested immune complex glomerulonephritis due to chronic graft-versus-host disease (GVHD) after bone marrow transplantation. In murine experimental chronic GVHD, anti-nuclear antibodies, which generate immune complexes that deposit or form in the kidney have been detected.