Ankylosing spondylitis (AS) is a chronic inflammatory disease that primarily affects the axial skeleton, leading to pain, stiffness, and reduced functional capacity. This study aimed to systematically review the effects of exercise therapy on patients with AS, with a focus on its role in enhancing spinal mobility, reducing pain, and improving functional independence and psychosocial well-being. A comprehensive literature review was conducted using databases including PubMed, Embase, Cochrane Library, CINAHL, and KoreaMed. Studies published between January 2000 and May 2025 were screened based on predefined inclusion and exclusion criteria. The methodological quality of selected studies was assessed using standardized tools, and a narrative synthesis was performed. A total of 8 studies were included. The findings consistently demonstrated that various forms of exercise including stretching, strengthening, aquatic therapy, and home-based programs were effective in improving spinal mobility, reducing disease activity, and enhancing quality of life in AS patients. Group-based and aquatic exercises were particularly beneficial for functional improvement and adherence. Exercise therapy plays a critical role in the management of AS and should be considered an essential component of long-term care. Future high-quality randomized controlled trials and meta-analyses are needed to further establish optimal exercise modalities and quantify their effectiveness. Multidimensional interventions that incorporate psychosocial and functional aspects are also recommended.