Empirical evidence has shown the relationship between alcohol abuse and the impairment of certain cognitive abilities. The aim of this paper was to analyze the influence of alcohol abuse on adolescents’ cognitive performance. Several questionnaires were used to assess adolescents’ addictive profile, as well as their performance on tasks involving cognitive abilities, such as attention, perception and reasoning. A total of 42 students, from an initial sample of 246 adolescents, completed the follow-up. Participants, aged between 16 and 20, were classified in two groups (21 consumers at risk and 21 consumers at low risk) and followed for one year. Results showed an increase of alcohol, tobacco and cannabis use during the follow-up. Considering data from both initial and final assessment, adolescents who met abuse criteria showed worse results than those with a non-abusive use in the Perceptual Ability Test (p<0,05). Future studies, with a larger sample size and a longer follow-up, are necessary to confirm the trends presented in this paper.