In Attention Deficit Hyperactivity Disorder (ADHD) agreement between parents and teachers is often low. Parental depressed mood and parenting stress are considered to decrease informant agreement. This study examined informant agreement in children with ADHD and the association between parental depressed mood, parenting stress and agreement in the ratings of ADHD, ODD and CD symptoms. Method: 65 parents completed questionnaires on ADHD behavior of their child, parenting stress and depressed mood, teachers reported on ADHD behavior. Results: Low agreement was found for hyperactive and moderate agreement for inattentive, ODD and CD symptoms. Stepwise regression analyses showed that parenting stress, and not parental depressed mood accounted for 12% of the variance in inattention symptoms disagreement, 14% of the variance in hyperactive symptoms disagreement and 9% in oppositional behavior disagreement. No significant predictors were found for CD disagreement. The found effect was independent of stimulant medication use. Conclusion: Parenting stress, but not parental depressed mood, was associated with the disagreement between parents and teachers on both ADHD and ODD symptoms. These results emphasize the importance of considering parenting stress in diagnosing ADHD and comorbid ODD.