Sympathetic skin potentials were recorded from the hand and genital region in 14 normal potent men and 18 patients with premature ejaculations. With the penis flaccid the sympathetic skin potentials obtained did not differ significantly in both groups. However, when erection was induced by 50 mg. intracavernous papaverine injection, the genital sympathetic skin potentials were significantly suppressed in all but 3 normal men, while the hand potentials did not change. In subjects with premature ejaculation genital and hand sympathetic skin potentials were suppressed during erection as a generalized bodily reaction except in 1 patient. This phenomenon may indicate that the specific and regional suppression of genital sympathetic activity during erection could not be properly adjusted in patients with premature ejaculation.