Autoimmune diseases represent a significant global health burden, characterized by aberrant immune responses leading to tissue damage and functional impairment. Despite advancements in immunosuppressive therapies, achieving sustained remission remains challenging, necessitating innovative therapeutic approaches. Chimeric antigen receptor (CAR) T cell therapy, a groundbreaking immunotherapy originally developed for oncology, has emerged as a promising strategy in the treatment of autoimmune diseases. By engineering autologous or allogeneic T cells to target specific immune components, CAR-T cell therapy has demonstrated profound efficacy in preclinical and clinical studies across diverse autoimmune disorders. Early clinical applications in refractory systemic lupus erythematosus highlight its potential to induce durable immune reprogramming, achieving drug-free remission and resolving multiorgan involvement. Moreover, its success extends to other autoimmune disorders, including systemic sclerosis, myasthenia gravis, and rheumatoid arthritis. However, challenges such as immune-related toxicity, persistence of therapeutic cells, and antigen escape remain key barriers. This review synthesizes recent advancements in CAR-T technology, clinical outcomes in autoimmune disease trials, and emerging strategies to optimize safety and efficacy, underscoring the transformative potential of CAR-T cell therapy in revolutionizing autoimmune disease management and highlighting the need for further large-scale clinical trials to realize its full clinical applicability.