Objective: Attention deficit hyperactivity disorder (ADHD) affects development and functionality of children in almost all fields including learning, behavior, family and peer relationships, physical safety and emotional progress. Except for this data, it is stated that preschool children with ADHD can differ from typically developing children in terms of their executive functions. In this study it is aimed to evaluate executive functions of preschool (36-71 months) ADHD cases by comparing these outcomes with control cases. Methods: In our study 47 ADHD and 47 healthy control cases are included. ADHD group is made up of cases who refer to Ege University Faculty of Medicine Child and Adolescent Psychiatry 0-6 Age Outpatient Clinic. DSM-IV criteria used for diagnostic assessment of ADHD. Behavior Rating Inventory of Executive Function-Preschool Version (BRIEF-P) administered by parents of cases. Results: In comparison of ADHD and healthy control group we have found difference in all BRIEF- P scales. The biggest effect size values were observed in inhibition, working memory, inhibitory self-control and emergent metacognition. Conclusion: As result of our study it was detected that preschool ADHD cases differ from healthy controls with regard to executive functions. It is important to support executive functions and take care of enhancing appropriate therapeutic strategies as from preschool years in children with ADHD, and also to prevent from long term problems like social, academic and self-regulation areas that can occur in this children.