Objective: Research results on the nature of sleep problems in children with ADHD are highly inconsistent. It is frequently reported that children with ADHD show more night-to-night variability in sleep than their typically developing (TD) peers, but this finding is also inconsistent. Lack of methodological control may account for these inconsistent findings. The current study examined the night-to-night variability of sleep between TD children and children with ADHD who were rigorously diagnosed, medication naïve, and free from comorbid mental health disorders. Method: Sleep parameters were analyzed for night-to-night variability across 4 weekday nights using actigraphy in 50 children with ADHD and 50 age- and sex-matched TD children. Results: There was a significant night-to-night variability for only sleep duration, but this was similar in both groups. Conclusion: These findings suggest that sleep problems in children with ADHD are not due to greater variability in sleep parameters relative to their TD peers.