BACKGROUND: There has been increased interest in pain neuroscience education (PNE) as a therapeutic approach for the management of fibromyalgia (FM). METHODS: A multicentre randomized, open-label, controlled trial was conducted to assess the effectiveness of a structured group intervention based on PNE in patients with FM. A total of 139 patients were included in the study and randomized to the intervention group (7 group sessions of education in neurobiology of pain) or to the control group (treatment as usual only). The primary outcome was the improvement of functional status and pain measured with the Fibromyalgia Impact Questionnaire (FIQ), and secondary outcomes were the reduction in the impact of pain and other symptoms (catastrophizing, anxiety and depression) and number of patients reaching no worse than moderate functional impairment (FIQ score <39). Differences between groups were calculated by linear mixed-effects (intention-to-treat approach) and mediational models through path analyses. RESULTS: At 1 year, improvements in FIQ scores were higher in the intervention group with moderate or high effect size, and decreases of ≥20% in 69.1% of patients (20.9% in the control group) and of ≥50% in 39.7% (4.5% in the control group). Also, 52.9% of patients had a FIQ <39 points (13.4% in the control group). CONCLUSIONS: In this sample of patients with FM, the improvement in quality of life and control of symptoms obtained by adding a PNE intervention showed promising results, equalling or surpassing previously reported outcomes. SIGNIFICANCE: A structured group intervention based on pain neuroscience education for 1 year in patients with fibromyalgia was associated with significant amelioration of the impact of the disease on scores of the Fibromyalgia Impact Questionnaire, the Health Assessment Questionnaire, the Hospital Anxiety and Depression Scale, the Pain Catastrophizing Scale and the Polysymptomatic Distress Scale as compared with only treatment as usual. These findings are clinically relevant considering the challenges posed by fibromyalgia to clinicians and patients alike.