Objectives: Chronic pain, often defined as pain lasting longer than three months, can lead to significant medical, social, and economic consequences, lost productivity, and larger health care costs. Chronic pain patients increasingly seek treatment through mindfulness meditation. Our aim was to synthesize evidence on efficacy and safety of mindfulness meditation interventions for the treatment of chronic pain. Methods: We searched electronic databases and systematic review bibliographies for randomized controlled trials (RCTs) on mindfulness for adults with chronic pain. We dually abstracted data and conducted efficacy meta-analyses. Quality of evidence was assessed using the GRADE approach. Results: 28 RCTs met inclusion criteria; only three reported on safety. We found low quality evidence that mindfulness meditation is associated with a decrease in pain compared to control in 24 RCTs. Mindfulness meditation significantly reduced pain scores compared to treatment as usual, but not compared to passive controls or education/support groups. The efficacy of mindfulness meditation on pain did not differ systematically by type of intervention, medical condition, length or frequency of intervention, or whether offered as mono- or adjunctive therapy. Statistically significant effects were also found for depression, and health-related quality of life. Conclusions: Mindfulness meditation improves pain symptoms, depression, and quality of life; however, quality of evidence for pain outcomes is low due to substantial heterogeneity and mixed quality of included RCTs. Additional trials with adequate power, greater efforts to prevent attrition, monitoring of adherence to meditation practice, active collection of adverse events, and better reporting of methods are suggested.