Cavernosometry has been utilized to diagnose vasculogenic impotence, especially, corporal venous leakage. However, it remains controversial in the cavernosometry including different techniques, parameters, normal and abnormal values. In addition, cavernosometry using papaverine and/or phentolamine can cause some untoward effects. We performed PGE1 cavernosometry with continuous monitoring of intracavernosal pressure(ICP) in 15 healthy volunteers and 69 impotent patients to elucidate relatively simple and safe method and to investigate effective parameters for the diagnosis of venogenic impotence. Of total 84 subjects, there was no priapism or penile hematoma. Pain was observed in 17(20%) subjects, and ecchymosis on injection site of 12(14%) subjects, respectively. Regarding parameters of cavernosometry for the differential diagnosis of impotence, there was no difference in the values of time taken from PGE1 injection to maximal ICP among normal, psychogenic, neurogenic and venogenic impotence group. However, venogenic group showed lower values of maximal ICP and higher decreasing rate of maximal ICP for successive 30 minutes than other groups(p<0.05). These results suggest that PGE1 cavernosometry with continous monitoring of ICP is relatively safe and noninvasive procedure. And parameters with maximal ICP and its decreasing rate in that procedure may provide important guideline for differentiating between venogenic and other nonvasculogenic impotence.