Abstract: Liquid-crystal system consists of egg yolk phospho-liqid (PC) and little water was studied by means of the small angle X-ray scatter (SAXS), in methanol, ethanol or isobutynol. Experments show thet layer distance decreases as the alcohol content increases in the system studied (5% H_2O-PC-alcohol) and as the hydrocarbon chain or branched chain increased in these alcohols, the layer distance is decreased. We consider that these changes might be in consequnce of the changes of molecule or force in the system. For this reason, it might be plausible that drinking a lot of alcohol would distroy the structure of biological liquid-crystal in the humanb boby and make human boby poisoning.