It has been reported that acute, simultaneous injections of taurine and ethanol were effective in reducing ethanol-induced locomotor activity and sleep time. The possible involvement of taurine administration in ethanol-induced conditioned taste aversion (CTA) was investigated. The results obtained in the present study following simultaneous administration of taurine (45 mg/kg) and ethanol (0.8, 1.2, and 1.6 g/kg) demonstrate a significant interaction between taurine and ethanol in their effect on ethanol-induced CTA in rats. This interaction was biphasic in nature and dependent upon the specific dose of ethanol. At the lowest ethanol dose (0.8 g/kg), which in itself resulted in a marginal CTA, taurine significantly enhanced the CTA induced by this dose. The intermediate ethanol dose of 1.2 g/kg produced a significant CTA. This CTA was blocked by administration of taurine. Finally, the CTA produced by the high dose of ethanol (1.6 g/kg) was not affected by administration of taurine. Taurine by itself does not produce a CTA. Peripheral levels of ethanol were ethanol dose dependent and the same in all animals regardless of treatment, indicating taurine had no effects on plasma ethanol levels. These data are similar to those obtained by earlier studies on the effects of taurine on ethanol-induced motor activity in mice. The present results support the findings reported by other investigators that taurine administration exerts a significant effect on ethanol-induced behaviors.