Objective: To identify impairment of executive functions (EF) in children with attention deficit hyperactivity disorder (ADHD). Subjects and methods: A case-control study was performed on a sample of schoolchildren with low socioeconomic levels in Bogota, Colombia. ADHD was diagnosed using the DSM IV checklist and the Behavior Assessment System for Children scale. Children with cognitive deficits were excluded. We evaluated scores from six measurements of executive function (EF). We conducted a bivariate statistical analysis to compare the variables, a multivariate study controlled by sex and age, and a logistic regression analysis. Results: The study sample included 119 children with ADHD and 85 controls, all aged between 6 and 12 years. Controlling by sex, age, and type of school showed that EF measurements in children with ADHD were significantly more impaired than in controls, especially for measurements of verbal and graphic fluency, Rey-Osterrieth Complex Figure, and cognitive flexibility. Comparison of ADHD subgroups showed that results in children with multiple deficits were similar to those in the global ADHD group. Graphic fluency impairment was the sole impairment in cases with only attention deficit or only hyperactivity-impulsivity manifestations. Conclusions: EF measures in children with ADHD revealed more problems, particularly those having to do within planning, inhibition, working memory and cognitive control. Age and sex may affect the degree of EF impairment. © 2012 Sociedad Española de Neurología.