Clinical studies have shown that behavioral and electrophysiological abnormalities occur in some human infants born to alcoholic mothers. The present study used rats to evaluate the effects of prenatal ethanol exposure on locomotor behavior and two paradigms for the generation of auditory event-related potentials (ERPs). Pregnant rats were fed liquid diets, one group received alcohol and the other was a nutritional control. The offspring were allowed to mature prior to the electrophysiological and behavioral testing. Prenatal alcohol exposed rats showed significantly more locomotor behavior in the first 4 hours of their activity cycle than nonethanol exposed rats, although not over a subsequent 8-hour period. Evaluation of the electrophysiological data revealed that the prenatal alcohol exposed group had significantly longer latencies of their P1 and N1 ERP components, in the hippocampus, than the control group. These results support anatomical data suggesting that the hippocampus may be an important area in which to direct further study of what brain mechanisms may be altered by prenatal ethanol exposure in the rat.