Fibromyalgia is a prevalent chronic musculoskeletal disorder characterized by widespread pain, severe fatigue, sleep disturbances, and psychological symptoms such as anxiety and depression. Its prevalence in the general population is estimated at 2-4%, with women disproportionately affected. Beyond the burden of physical pain, fibromyalgia substantially impairs patients' quality of life, leading to social and occupational dysfunction. Pharmacological treatments demonstrate limited and inconsistent effectiveness, underscoring the need for complementary non-pharmacological approaches. Among these, psychological interventions have attracted increasing attention. The aim of this systematic review was to synthesize current evidence on the effectiveness of psychological interventions in reducing pain and improving quality of life in patients with fibromyalgia. A comprehensive search was conducted in PubMed, Scopus, Web of Science, and PsycINFO for articles published between 2000 and August 2025. The reviewed studies demonstrated that psychological interventions, particularly cognitive-behavioral therapy (CBT) and mindfulness-based therapies, produced significant improvements in pain reduction, sleep quality, depressive symptoms, and overall quality of life. Several studies further highlighted the benefits of group-based interventions in enhancing perceived social support and reducing stress. In contrast, evidence for other approaches, such as commitment therapy (ACT) and hypnotherapy, remains scarce and warrants further investigation. The findings suggest that psychological interventions represent valuable components of a multidimensional treatment strategy for fibromyalgia. These approaches not only alleviate physical symptoms but also address the psychological and social dimensions of the disorder. Nevertheless, substantial methodological heterogeneity and limitations in study design highlight the urgent need for rigorously designed, large-scale, long-term clinical trials to establish more definitive conclusions.