During the COVID-19 pandemic, there was an increase in online gaming behaviour among college students. This study aimed to examine the impact of online self-help interventions consisting of different components within the Acceptance and Commitment Therapy (ACT) framework on college students’ gaming disorder and gaming frequency. Additionally, it evaluated the effectiveness of both interventions in addressing psychological distress among college students during the COVID-19 pandemic. One intervention was a full ACT program, which consists of six core components, while the other intervention focused on the engaged components of ACT (specifically targeting value-based actions). The study employed a 2 conditions (Full ACT vs. Engaged ACT) × 3 times (pre-, mid- and post-program) design to examine the effectiveness of these interventions. Each intervention consisted of 10 sessions, delivered at a frequency of five sessions per week over a 2-week period for both groups. The participants in this study were enrolled in two online classes. Participants with gaming disorder scores in the top 20% were selected and assigned to either the Full group (N = 49) or the Engaged group (N = 41) for the interventions. The study assessed outcome variables, including gaming disorder, psychological flexibility, daily gaming hours, weekly gaming days and psychological distress, at pre-intervention, mid-intervention, post-intervention and one-month follow-up for both groups. No significant differences were observed between the two groups on these outcomes at the pre-intervention stage. The findings of this study indicate that both interventions effectively reduced gaming disorder and weekly gaming frequency, while enhancing psychological flexibility. Nonetheless, the Engaged group exhibited a significant reduction in daily gaming hours. There was no substantial change in psychological distress in either group during and after the intervention. The implications and limitations of this study were also reported.