Three nephroblastomas, including one bilateral tumour, have been detected in three children belonging to the same family and born from a consanguinous marriage. The clinical and diagnostic particularities compared to non familial "sporadic" nephroblastomas are studied. The pathogenesis with the incidence of chromosomal anomalies, the diagnosis and the frequency of bilateral diseases along with the associated deformities and a non invasive therapeutic attitude are discussed.