Objectives <p>Gay men experience disproportionately high rates of mental health challenges, coupled with reduced compassion. The present study evaluated the efficacy of Compassionate Mind Training for Gay Men (CMT-GM), a newly developed mental health support program including sexual minority affirmative components specifically targeting self-criticism and fear of compassion.</p> Method <p>A randomized controlled trial was conducted. Cisgender gay male adults were recruited. No mental health or psychiatric screening criteria were applied. A total of 182 participants were randomly assigned to either the CMT-GM group or the control group. CMT-GM consisted of a 150-min group-based seminar at the beginning, 30&#xa0;days of digitally audio-guided mindfulness and compassion-building individual practices, and a mid-program brief individual phone consultation. The primary outcome, psychological distress, was measured by a scale assessing depression, anxiety, and stress. Secondary outcomes such as self-criticism and fear of compassion were also measured. Participants completed the measures at baseline, post-program, and 1-month follow-up.</p> Results <p>In the CMT-GM group, compared with baseline, there were significant decreases in psychological distress, self-criticism, and fear of compassion at post-program and at 1-month follow-up, with medium-to-large decreases at 1-month follow-up. In the control group, there were no clear differences across time points. Both self-criticism and fear of compassion mediated the relationship between condition assignment and psychological distress, but the mediating effects of self-criticism were relatively robust.</p> Conclusions <p>CMT-GM, a scalable new program involving digital self-help components, can alleviate psychological distress among gay men. Future practice may utilize mindfulness and compassion-building components to support sexual minorities.</p> Preregistration <p>This study is not preregistered.</p>