Objective: An increasing number of studies suggest possible beneficial effects of exercise in alleviating ADHD functional outcomes. The current study provides a quantitative meta-analysis of the available studies investigating this relationship. Method: Studies reporting on the effects of physical exercise on motor skills and executive functions in children with ADHD were identified through Cochrane, PsycInfo, PubMed, Web of Science databases. Ten publications were selected. Random-effects model was used to calculate effect sizes. Results: There was a significant effect of exercise on ADHD functional outcomes (g = 0.627). Longer exercise intervention duration was consistently associated with larger effect sizes. Effect sizes were not related to exercise intensity, mean age of participants, or gender distribution. Conclusion: Results suggest that exercise has a modest positive impact on ADHD functional outcomes, such as executive functions and motor skills, with longer interventions yielding better results.