<p>This study examined how parents’ attention-deficit/hyperactivity disorder (ADHD) tendencies, boredom proneness, and parenting styles are associated with their children’s ADHD tendencies and boredom proneness, which have been scarcely studied empirically. Middle-class individuals aged 30–50 years with children in the first-to-third year of elementary school were recruited, and data from 301 parent–child pairs were analyzed. Parents reported their own ADHD tendencies, boredom proneness, and parenting styles, as well as their child’s ADHD tendencies, boredom levels, and academic performance. Data on parents’ educational background and income levels were also collected as supplementary information. Mothers’ and fathers’ ADHD tendencies, boredom proneness, and parenting styles were differentially associated with their children’s ADHD tendencies and boredom proneness. High ADHD tendencies in children were effectively explained by maternal responsiveness. Additionally, paternal responsiveness interacted with a child’s ADHD, significantly increasing the child’s boredom level, while maternal control appeared to have an inhibitory effect on boredom. This was among the first to demonstrate the influence of parental variables on children’s ADHD tendencies and boredom proneness. These findings contribute to a better understanding of how parental factors are associated with children’s ADHD tendencies and boredom proneness, and may help inform coping strategies for children.</p>