The current study examined the role of self-reported and child-reported maternal lack of acceptance in increasing the likelihood of developing internalizing and externalizing symptoms among children with ADHD symptomatology. The effects of a social desirability bias on mother’s self-reports of rejection were controlled for. Mother-child agreement about parenting behaviors like warmth/affection, hostility/aggression and indifference/neglect was also investigated. In addition, variables with the potential to affect agreement (i.e., parents’ social desirability bias, child age, child sex) were examined. Participants included 120 boys and 90 girls, 6 to 11 years old (M = 8.25, SD = 1.18) with and without ADHD and their primary parent/guardian (N = 209). Parent and child participants completed self-report instruments separately. Results indicate that the relationship between mother-and-child-reported ADHD symptoms and internalizing symptoms is strongest when mothers exhibit low levels of rejection. Among the ADHD subsample, maternal lack of acceptance acts as a risk factor by strengthening the relationship between hyperactive/impulsive symptoms and externalizing symptoms. In addition, mothers and their children report significantly different levels of parenting behaviors. Child age and child sex were significant predictors of parent-child disagreement.