Purpose: To determine the changes of erectile response to repeated audiovisual sexual stimulations. MATERIALS AND METHODS: The same erotic video was consecutively exposed to 42 men (20 patients with psychogenic impotence and 22 normal men) for 3 days at an interval of 1 day. The erectile response during the audiovisual stimulation was monitored using Rigiscan and maximal rigidity of the erection which sustained for more than 5 minutes was measured. The rigity on the first, second and third day was comparatively analyzed. Whether previous multiple exposure to the erotic movie or exposure to the same or similar movie influence the erectile response was also evaluated. RESULTS: The rigidity on the third day test was significantly decreased to that on the first day test in both psychogenic impotence patients and normal control (p<0.05), in both the group of multiple exposures and the group of less exposures (0.05), in both the group exposed and the group not exposed previously to the same or similar movie (p<0.05). The rigidity on the first day test was significantly lower in the group of multiple exposures than in the group of less exposures (p<0.05). However, the rigidity was not significantly different between the group exposed and the group not exposed previously to the same or similar movie on the first day test. CONCLUSION: Real time monitoring of penile erection during audiovisual sexual stimulation may result in false negative response when the patients exposed to the stimulation repeatedly.