Background: Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common chronic disorders, which influence millions of children worldwide. It is a neuro-developmental disorder that has a great impact on children in a critical period of development, the treatment of which extends over years. Aim: This study examined the association between sleep habits and quality of life in children with ADHD. Methods: By using, a descriptive cross-sectional study conducted on one hundred sixteen of children with ADHD attending the child psychiatric outpatient clinic of Mansoura University Hospitals. Three tools were used for data collection: A structured questionnaire of the socio demographic and clinical features, the Children’s Sleep Habits Questionnaire (CSHQ), and the Pediatric Quality of Life Inventory (PedsQLTM). Results: The total mean (±SD) of sleep habits was 64.77 ±18.43. The studied children rated themselves significantly better than their parents in all domains of PedsQLTM (P < 0.0001) and there were statistical significant associations between CSHQ score and PedsQLTM score (P≤0.001). Conclusion and recommendation: Sleep disorders are significantly associated with poor physical and psychosocial quality of life. It is possible that such sleep interventions in children with ADHD can enhance their quality of life.