The present study examined the influence of fathers’ parenting quality during infancy on children’s emotion regulation during toddlerhood and, subsequently, attention-deficit/hyperactivity disorder (ADHD) symptoms in middle childhood. Fathers and their 8-month-old infants (N = 124) were followed over time to obtain home observations of parenting quality at 8 and 24 months, laboratory observations of children’s emotion regulation at 24 months, and teacher reports of children’s ADHD symptoms at 7 years. A path analysis revealed that fathers’ emotional disengagement in infancy and minimizing responses to children’s distress in toddlerhood forecast children’s development of ADHD symptoms in middle childhood. Further, a significant indirect effect was found such that fathers’ parenting at 8 and 24 months predicted subsequent development of ADHD symptoms at age 7 through toddlers’ difficulty regulating emotion. Implications of this study for early intervention and directions for future research are discussed.