ObjectivesThere is an increasing recognition of mindfulness-based interventions (MBIs) as a promising way to reduce burnout. However, inconsistent results were found on the effect among college students. In addition, the underlying mechanisms remain unclear. The aims of this study were to explore the effect of a mindfulness-based training program on burnout in college student population and to examine if changes in mindfulness mediate the intervention effect.MethodA total of 128 college students (M = 21.36 years, SD = 2.76 years) were randomized into an intervention group (n = 64) or a wait-list control group (n = 64). The intervention consisted of eight sections of mindfulness training courses. Measures on mindfulness and burnout were administered at the baseline, post-intervention, and 3-month follow-up.ResultsCompared to those in the control group, participants in the intervention group reported a significant increase in mindfulness and a decrease in burnout both at post-intervention (mindfulness: F = 22.41, p < 0.01, partial eta(2) = 0.15; burnout: F = 8.24, p < 0.01, partial eta(2) = 0.06) and 3-month follow-up (mindfulness: F = 16.29, p < 0.01, partial eta(2) = 0.12; burnout: F = 9.24, p < 0.01, partial eta(2) = 0.07). Mediation analyses demonstrated that the increase in mindfulness fully mediated the intervention effect on burnout.ConclusionsMindfulness-based training programs can effectively reduce burnout among college students, and the effect appears to be mediated by changes in mindfulness levels.PreregistrationThis study is not preregistered.