Polyorchidism is a rare anomaly with approximately 70 cases reported in literature. The exact explanation for the production of polyorchidism is not known, although several theories have been proposed, including anomalous appropriation of cells, initial longitudinal duplication of the genital ridge and transverse division of the genital ridge, either through some local accident of development of peritoneal bands. A functional classification based upon the embryogenic development is provided. Type I: the supernumerary testis lacks an epididymis and vas. The split-off part of the primordial gonad does not communicate with the mesonephric tubules from which the epididymis develops. Type II: the supernumerary testis is linked to the regular testis by a common epididymis and shares a common vas with it. The division of the genital ridge occurs in the region where the primordial gonads are attached to the mesonephric ducts, although the latter are not divided (incomplete division). Type III: the supernumerary testis has its own epididymis but shares the vas with the regular testis. This variant results from a complete transverse division of the genital ridge. In the majority of the reported cases, the patients are asymptomatic and have painless groin or testicular masses. Approximately 50% occur as maldescent or cryptorchidism, and about 30% are associated with indirect hernia. The remaining 20% are discovered variously in relation to torsion, or are associated with hydrocele, epididymitis, varicocele or infertility. Moreover, since there is a 20 to 40 fold increase in testicular malignancy in patients with cryptorchidism compared with the normal testis, tumours of the supernumerary testicles are not unusual. We reported two cases of polyorchidism: the first patient is probably a longitudinal division of the genital ridge and the second is a completely duplication of the primordial gonads. The patients described vague, intermittent, testicular pain. Physical examination and the scrotal sonography and magnetic resonance revealed in the first patient a supernumerary testis in the right scrotal space and in the second a bilateral double testis. In conclusion we think that in the absence of any concomitant disorder and if testicular tumor can be ruled out by ultrasonography and magnetic resonance imaging, surgical exploration with biopsy is unnecessary.