The relationship between executive function and comorbid diagnoses in ADHD children is examined. One hundred six children between 7 and 15 years of age are assessed using the Tower of London (TOL), a test of executive function, and the Kiddie Schedule of Affective Disorders and Schizophrenia, Present and Lifetime Version, a diagnostic interview. All children met the diagnostic criteria for ADHD. A majority of the children had comorbid anxiety disorders, mood disorders, or oppositional defiant disorder. Measures on the TOL are total move score, total initiation time, and total rule violations. Age is predictive in all three measures of executive function as assessed by the TOL. Gender is predictive of total initiation time and total rule violations. Comorbid disorders are found to not have significance on executive function as measured by the TOL. This study concludes that comorbid disorders may not affect executive function. (Contains 6 tables.)