Graves' disease was initially diagnosed in an 11-year-old Chinese boy in March 1989. After regular propylthiouracil (PTU) and thyroxine, he achieved a euthyroid state. Heavy proteinuria with class IV lupus glomerulonephritis, anemia, arthralgia, low serum complement and anti-dsDNA (+) appeared 15 months later. Thyrotoxicosis also relapsed at this time. His condition fitted the diagnostic criteria of systemic lupus erythematosus. His antimicrosomal antibody titer was 1:1,600 (+) thyroid-stimulating hormone receptor antibody level was strongly positive, and the titer of antiinsulin antibody was high as well. These clinical, laboratory and histological findings indicate that class IV lupus nephritis may be associated with Graves' disease.