An experimental study was performed to investigate. The subjects drank 0.5g/kg ethanol and performed 7 items of SPES(simple reaction time, color word stress, digit classification, finger tapping speed, numerical ability, symbol digit coding, memory digit span). 20 students of medical college participated in the study during August, 1996. After ethanol intake, performance of 4 items(simple reaction time, digit classification, finger tapping speed, symbol digit coding) significantly showed to be decreased. The function of perception - response speed and steady movement were found to be more sensitive to ethanol than that of short - term memory, numerical ability and specification of color. No significant association were found between smoking, alcohol drinking, BMI(body mass index) and the effects of ethanol on neurobehavioral performance.