Two male cases with Wilms' tumor in association with ambiguous genitalia and nephrotic syndrome are described. Seventeen similar cases reported in the literature are also analyzed. In these patients, nephrotic syndrome was noticed at younger ages, and progressed more rapidly than usual. Renal damage was so serious that at least 11 out of 9 patients died of renal failure, though not of Wilms' tumor itself. It should be stressed that the clinical course and associated anomalies were quite similar among these patients. We suggest that Wilms' tumor, ambiguous genitalia and this type of nephrotic syndrome may have some etiologic connection.