Objectives <p>High prevalence of depression in young adults indicates the importance of finding effective treatments for this population. Mindful yoga has shown promise as a mood disorder intervention, but there remain gaps in the knowledge base, such as the mechanisms of action. These studies examined whether a short mindful yoga intervention led to greater reductions in depressed affect, compared to an active control group, and whether this effect was mediated by rumination and attentional bias.</p> Method <p>In Study 1, undergraduates (<i>n</i> = 71) received nine sessions of mindful yoga or relaxation. In Study 2, undergraduates (<i>n</i> = 74) selected for symptoms of depression followed the same procedure as Study 1.</p> Results <p>In Study 1, results indicated no group differences on depressed affect at post-intervention or at 2-month follow-up. Post-hoc moderation analyses showed that for participants with greater depressed affect at baseline, mindful yoga was more effective in reducing depressed affect at post-intervention and 2-month follow-up. In Study 2, at 2-month follow-up, but not at post-intervention, mindful yoga led to greater reductions in depressed affect. Neither study showed mediation effects for rumination or attentional bias.</p> Conclusions <p>The results suggest mindful yoga may have promise for young adults with symptoms of depression.</p> Preregistration <p>This study was not preregistered.</p>