Experimental induction of polycystic ovary (PCO) in rodent resembling some aspects of human PCO syndrome was produced using the long-acting compound estradiol valerate (EV). Our previous study on the role of Korean red ginseng total saponins in a steroid-induced PCO rat model demonstrated that electro-acupuncture modulates nerve growth factor (NGF) concentration in the ovaries. In fact, the involvement of a neurogenic component in the pathology of PCO-related ovarian dysfunction is preceded by an increase in sympathetic outflow to the ovaries. In the present study, we tested the hypothesis that Korean red ginseng extract (KRGE) administration modulates sympathetic nerve activity in PCO-induced rats. This was done by analyzing NGF protein and NGF mRNA expression involved in the pathophysiological process underlying steroid-induced PCO. EV injection resulted in significantly higher ovarian NGF protein and NGF mRNA expression in PCO-induced rats compared to control rats, and PCO ovaries were counteracted by KRGE administration with significantly lower expression of NGF protein and NGF mRNA compared to EV treated ovaries. These results indicate that EV modulates the neurotrophic state of the ovaries, which may be a component of the pathological process by which EV induces cyst formation and anovulation in rodents.