Background This umbrella review summarizes the evidence across meta-analyses regarding the effectiveness and adverse effects of deep brain stimulation (DBS). Methods Databases were searched up to March 2015 for meta-analyses of comparative trials in humans assessing the effectiveness or adverse effects of DBS. Data selection, data extraction, and risk of bias assessment were performed by two independent reviewers. Results Seven eligible systematic reviews were included assessing the use of DBS for epilepsy (n = 1), obsessive-compulsive disorder (n = 1), and Parkinson disease (n = 5). The summary estimates were significant at p ≤ 0.05 in four meta-analyses (27%) with both fixed and random effects. One meta-analysis reported that DBS was more effective than sham in reducing the Yale-Brown Obsessive Compulsive Scale score in obsessive-compulsive disorder patients. The remaining three meta-analyses reported differences regarding mortality and depression in patients with Parkinson disease between DBS of the subthalamic nucleus and of the globus pallidus internus. Of the 15 meta-analyses, none compiled adequately robust evidence. Conclusions Although DBS has emerged as a viable surgical intervention to treat various disabling neurologic symptoms, existing studies fail to adequately support its use based on robust evidence without hints of bias.