We conducted a meta-analysis to investigate the effectiveness of interventions aimed at reducing teacher burnout. Online and reference list searches yielded 513 unique results, and the final sample contains 23 controlled trials (19 journal articles and 4 unpublished dissertations). More than two thirds of the studies had optimal quality, and the risk of bias was not related to the overall effectiveness of the interventions. The overall effects were small, but statistically significant (d = 0.18, SE = 0.05, Z = 3.26, p < 0.001, k = 23). Separate analyses on each burnout component showed similar intervention effects on emotional exhaustion and personal accomplishment, but almost null effects on depersonalization (d = 0.03, SE = 0.06, Z = 0.53, p > 0.05, k = 11). Additional moderator analyses suggested that mindfulness interventions had significant effects on exhaustion and personal accomplishment. Interventions on primary and middle school teachers reported effect sizes below the average effect. Similar to previous findings, interventions that lasted less than 1 month had the smallest levels of efficacy.