This study examined parenting stress among parents of adolescents with Attention-Deficit Hyperactivity Disorder (ADHD). The sample comprised 138 adolescents (84 ADHD, 52 boys, 32 girls; 54 non-ADHD, 24 boys, 30 girls) age 13 to 18 and their parents. Mothers (n = 135) and fathers (n = 98) of participating teens completed the Stress Index for Parents of Adolescents. Mothers and fathers of adolescents with ADHD reported more stress than parents of adolescents without ADHD with regard to their children’s challenging behaviors (Adolescent domain stress). Mothers of adolescents with ADHD also reported that they experienced elevated levels of stress in terms of role restrictions, feelings of social alienation, conflict with their partner, feelings of guilt and incompetence (Parent domain stress), and relationship with their children (Adolescent-Parent Relationship domain stress; APR). The extent to which clinical levels of adolescent Oppositional Defiant Disorder (ODD) symptoms or externalizing behavior in general were associated with parenting stress depended on the rater of these behaviors. Parenting stress was associated with higher levels of ODD and other externalizing behaviors when these behaviors were rated by parents but not when they were rated by teachers. In addition, over and above adolescent ADHD classification, mothers’ self-reported ADHD symptoms were associated with higher parenting stress in the Adolescent and Parent domains, and fathers’ self-reported ADHD symptoms were associated with lower APR stress. The results suggest directions that should be considered for addressing parenting stress when designing interventions for families of adolescents with ADHD.