To determine the value of color duplex scanning in the diagnosis of venogenic impotence we examined 53 patients. The control population consisted of 26 psychogenically impotent men and 8 normal potent men who all had a firm erection after pharmacological stimulation. There was no significant difference in the values of duplex parameters between these 2 groups. The venous leak population was characterized by a bad erectile response to pharmacological stimulation despite a good arterial compliance and by a persistent diastolic flow as shown by duplex scanning. There was a significant difference with the control population for the parameters of resistance index after 10 minutes (p = 0.001), minimal resistance index (p = 0.016) and corporeal volume increase (p = 0.010). There was a good correlation between the results of duplex scanning and those of pharmacocavernosography-pharmacocavernosometry (93%). We conclude that dynamic color duplex scanning can be used as a screening procedure to diagnose significant venous leakage in an objective manner with the resistance index.