Background: Considering the importance of Executive Functions to clinical and nonclinical situations, Barkley proposed a new theory of executive functioning based on an evolutionary neuropsychological perspective and clinical research using large samples of clinical and community identified adults and children as well as children with ADHD followed to adulthood. Objective: The present study aims to adapt the Barkley Deficits in Executive Functions Scales (BDEFS) to Brazilian Portuguese and also assess its construct validity in a sample of normal Brazilian adults. Methods: The original version of scale was adapted to Brazilian Portuguese according to the guideline from the ISPOR Task Force. To assess the semantic equivalence between the original and adapted version, both of them were applied into a sample of 25 Brazilian bilingual adults. Finally, 60 Brazilian adults completed the BDEFS and the Brazilian versions of Barratt Impulsiveness Scale (BIS-11) and Adult Self-Report Scale (ASRS-18) to assess convergent validity. Results: The BDEFS Brazilian Portuguese version has semantic correspondence with the original version indicating that the adaptation procedure was successful. The BDEFS correlated significantly with the impulsivity and attention scores from the BIS-11 and ASRS-18 supporting its construct validity. Cronbach’s alpha (α = 0.961) indicated that the BDEFS translated version has satisfactory internal consistency. Discussion: Together, these findings indicate the successful adaptation of the BDEFS to Brazilian Portuguese and support its utility in that population.