Neurocognitive functions are indispensable faculties for daily, social and working life. Objective: Prevalence of altered cognitive functions in patients recovering from drug addiction and alcoholism using the Neuropsychological Battery NEUROPSI. Methodology: exploratory, non-experimental, observational research based on the Neuropsi brief neuropsychological assessment instrument in Spanish. Contribution: in a sample of 20 participants, the following results were obtained: 60 % of the population studied showed alterations in neurocognitive functions, 15 % showed mild alterations, 25 % showed noderate alterations and the other 20 % showed severe alterations. On the other hand, the population within normal parameters (40 %) presented low scores in reading comprehension, attention and concentration.