Objective: In spite of an expanding use of health-related quality of life assessment in research and treatment of ADHD, there is still limited knowledge about the role of impaired quality of life in symptomatic outcomes. This study investigates how specific functional domains affect the relationship between ADHD symptoms and occupational outcome. Method: A total of 149 referred adults with ADHD participated in the study. We used mediation analyses to test a model with two 36-item short form health survey (SF-36) Mental Component scales, that is, role-emotion function and social function as mediators for the relationship between ADHD inattentiveness and occupational outcome. Results: The relationship between ADHD inattentiveness and occupational outcome was completely mediated by both role-emotion function and social function. Conclusion: Role-emotion function and social function may identify specific aspects of functional impairment as potentially important treatment targets for ADHD patients with impaired occupational function. (J. of Att. Dis. 2013; XX(X) 1-XX)