Objectives: This paper presents a systematic review and meta-analysis of the effectiveness of mindfulness-based stress reduction (MBSR) for FMS. Methods: The PubMed/MEDLINE, Cochrane Library, EMBASE, PsychINFO and CAMBASE databases were screened in September 2013 to identify randomized and non-randomized controlled trials comparing MBSR to control interventions. Major outcome measures were quality of life and pain; secondary outcomes included sleep quality, fatigue, depression and safety. Standardized mean differences and 95% confidence intervals were calculated. Results: Six trials were located with a total of 674 FMS patients. Analyses revealed low quality evidence for short-term improvement of quality of life (SMD=-0.35; 95% CI -0.57 to -0.12; P=0.002) and pain (SMD=-0.23; 95% CI -0.46 to -0.01; P=0.04) after MBSR, when compared to usual care; and for short-term improvement of quality of life (SMD=-0.32; 95% CI -0.59 to -0.04; P=0.02) and pain (SMD=-0.44; 95% CI -0.73 to -0.16; P=0.002) after MBSR, when compared to active control interventions. Effects were not robust against bias. No evidence was further found for secondary outcomes or long-term effects of MBSR. Safety data were not reported in any trial. Conclusions: This systematic review found that MBSR might be a useful approach for FMS patients. According to the quality of evidence only a weak recommendation for MBSR can be made at this point. Further high quality RCTs are required for a conclusive judgment of its effects.