Cystic dysplasia of the rete testis is a rare cause of paediatric scrotal mass often associated with other genitourinary tract anomalies. This benign congenital lesion is the result of a developmental disorder of the union of the Wolffian duct and the seminiferous tubules, and represents a diagnostically challenging condition. Cystic dysplasia of the rete testis should be considered in the differential diagnosis of paediatric scrotal masses. Treatment should be individualized for each case.