The effects of SDZ-205,152, a synthetic mixed D1/D2 dopamine receptor agonist, was investigated in rats trained to orally self-administer ethanol (10% w/v) in a free-choice, two-lever operant task. Pretreatment with SDZ-205,152, at doses of 0.5-5.0 mg/kg subcutaneously 30 min prior to limited access to 10% ethanol and water, selectively reduced ethanol-reinforced responding without affecting responses for water. These results demonstrate that ethanol-reinforced responding was attenuated by SDZ-205,152 and suggests that dopamine neural systems may mediate, in part, the reinforcing properties associated with voluntary ethanol self-administration.