On the precontracted rabbit cavernosal muscle strips with phenylephrine ($5ast10^{-6}$M), Increasing concentrations of acetylcholine (10-7, 10-6, 10-5, 10-4M) showed relaxation effect dose-dependently in control group ($10^{-7}$M : 15.32%, $10^{-6}$M : 35.44%, 10-5M : 59.45%, 10-4M : 76.54%). After 3 months administering Korean red ginseng, the relaxation action of acetylcholine was significantly increased ($10^{-7}$M : 34.18%, $10^{-6}$M : 56.35%, $10^{-5}$M : 75.33%, $10^{-4}$M : 89.86%). Relaxation effect of Korean red ginseng was significantly increased after 3 months administering Korean red ginseng. Intracavernous pressure response to electrostimulation wan 107.52 cm$H_2O$ in control group and significantly increased to 138.34 cm $H_2O$ after 3 month administering Korean red ginseng. With these results, we can confirm that long-term administration of Korean red ginseng enhances the erectly capacity and that its action is mediated by endothelium derived relaxing factor and peripheral neurophysiologic enhancement.