Objective: This pilot study examined the effectiveness of a parent-delivered intervention for improving: the social play skills of children with attention deficit hyperactivity disorder (ADHD) and their typically developing playmates and the empathy of children with ADHD. Methods: Participants were children with ADHD and their typically developing playmates (n = 9/group). The intervention was primarily parent-implemented and involved: parent-training, weekly home-modules, three clinic play-sessions, therapist-parent phone consultations and a one-month follow-up. The Test of Playfulness (ToP) was the primary outcome measure. Cohen’s-d and paired sample t-test calculations were used to measure effect. Results: Social play outcomes of children with ADHD improved significantly from: pre- to post-test (t = 3.2; p = 0.02; d = 1.0) and post-test to follow-up intervention (t = 2.7; p = 0.02; d = 1.1). Playmate’s improved significantly from pre- to post-intervention (t = 3.9; p = 0.03; d = 1.2). Children with ADHD improved significantly on 4/7 ToP empathy items (t = 2.31–3.16; p = 0.02). Conclusion: The intervention successfully improved the social play skills of children with ADHD and their playmates.