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Previous evidences demonstrate a higher reactivity to several effects of ethanol in developmentally low-level lead (Pb) exposed rats. This study aimed to evaluate the influence of cyanamide, a drug that modifies ethanol metabolism by inhibiting ALDH and to a lesser extent catalase, on the motivational and stimulant properties of ethanol. Thirty-five day-old male Wistar pups perinatally exposed to 220 ppm Pb were evaluated in their ethanol intake in a free-choice limited paradigm (2 h) at increasing ethanol concentrations (2-10%); immediately thereafter their ethanol-induced locomotor activity was assessed. Cyanamide was centrally and systemically administered in both tests. The results demonstrated that Pb-exposed rats voluntarily consumed more ethanol and showed ethanol-induced hyperlocomotion in relation to their respective controls, being both effects reversed by systemically-administered cyanamide. On the opposite, when cyanamide was administered centrally, only the control animals evidenced an increase in ethanol intake, although both groups showed an increase in ethanol-induced locomotor activity. The interplay between centrally-formed (reinforcing) and peripheral (aversive) acetaldehyde reveal the importance of ethanol metabolism in the higher motivational and stimulant effects observed in developmentally Pb-exposed rats.