Membranous glomerulopathy and proteinuria have occurred in patients receiving captopril for hypertension. In this case of captopril-associated nephrotic syndrome, a pretreatment biopsy specimen showed normal histologic appearance and glomerular ultrastructure. A posttreatment biopsy specimen showed membranous glomerulopathy. It seems likely that captopril caused the membraneous glomerulopathy.