Objectives <p>Mindfulness-based cognitive therapy (MBCT) integrates cognitive therapy and mindfulness meditation to help individuals disengage from maladaptive thoughts and reactive behavioral patterns. By cultivating nonjudgmental present-moment awareness and decentering from thoughts and emotions, MBCT enhances the capacity to respond more skillfully, thereby reducing impulsivity and promoting self-control. This study pilot-tested the effectiveness of MBCT for internet gaming disorder (MBCT-G) among college-aged students at risk for problematic gaming, focusing on reducing symptoms of internet gaming disorder and secondarily on psychological benefits.</p> Method <p>A pilot experimental study was conducted in South Korea with 46 college-aged students at high risk of internet gaming disorder. The intervention group (<i>n</i> = 24) participated in eight group sessions of MBCT-G and a control group (<i>n</i> = 22) received no intervention. Internet gaming disorder, impulsivity, depressive symptoms, perceived stress, anxiety, and self-control were assessed before and after the intervention and at 4 weeks postintervention. </p> Results <p>Linear mixed-model analyses indicated participants in the intervention group had greater reductions in internet gaming disorder symptoms, perceived stress, and state anxiety and enhanced improvement in self-control relative to the control group; these changes persisted at 4-week follow-up except for state anxiety.</p> Conclusions <p>Findings suggested MBCT-G is a promising intervention for college-aged students whose gaming is problematic and puts them at risk for gaming disorder. Further research is needed with a larger sample, a comparison group receiving an alternative intervention and a longer follow-up period.</p> Preregistration <p>This study was not prospectively registered; however, it was retrospectively registered with ISRCTN Registry (# ISRCTN17598517).</p>