Objectives: This review addresses important practical questions facing clinicians regarding internet gaming disorder (IGD) and attention-deficit/hyperactivity disorder (ADHD) in children and youth (C-Y). The authors investigated data concerning the risk that C-Y who have ADHD will develop IGD, whether effective treatment of ADHD positively influences the course of IGD in C-Y who have both, and other findings that might be of benefit to clinicians who treat C-Y with these conditions. Methods: We conducted a literature review using 4 databases: PubMed, Scopus, PsychInfo, and Embase. Results: C-Y with ADHD are at greater risk for developing IGD than those without ADHD. A close association exists between the severity of ADHD symptoms and the severity of IGD. It is unknown what proportion of C-Y with ADHD will develop IGD during their developmental trajectory; however, C-Y with IGD are at risk for developing ADHD, and ADHD can also increase the vulnerability of C-Y to IGD. Adolescents with ADHD and IGD have greater deficits in social skills than those with ADHD but no IGD. Lower parental occupational and socioeconomic status and poor family relationships are associated with more severe IGD symptoms. Atomoxetine and methylphenidate are equally effective in alleviating IGD symptoms comorbid with ADHD.Conclusions: C-Y with ADHD are at increased risk for developing IGD compared with C-Y without ADHD, but it has not been determined at what developmental stage IGD is likely to emerge. Since IGD and ADHD are strongly associated, it is imperative to consider ADHD as a significant risk factor for IGD and vice versa, which can help psychiatrists be alert for early signs of IGD and manage them accordingly.