The authors reviewed and analysed cavernosograms of 41 men with venous impotence to verify the multiplicity and to classify the main routes of leak veins. Among 41 cases the main routes of venous leks were Proper Cavernosal Vein(27 cases [66%]), Deep Dorsal Vein(24 cases [59%]), Crural Vein(22 cases [54%]), and Superficial Dorsal Vein(12 cases[29%]) in decreasing order. The multiplicity of leak veins were shown in 30 out of 41 cases(73%). To improve the success rate of ligation of all leaking veins, cavernosograms are essential as a preoperative study to verify the multiplicity and the main route of leaks.