Optic neuromyelitis optica (NMO) is increasingly recognized as an inflammatory demyelinating disease of the central nervous system with diverse clinical and imaging manifestations that primarily affects the optic nerve and spinal cord. The introduction of antibodies to aquaporin 4 (AQP4) has established NMO as a disease entity independent of multiple sclerosis. Currently, through numerous clinical observations and case reports, more than 30% of NMO patients are found to have one or more coexisting systemic autoimmune diseases (connective tissue diseases), such as systemic lupus erythematosus, dry syndrome, and Hashimoto’s thyroiditis. Compared with common NMO, NMO with combined connective tissue disease has the following characteristics: 1. 2. More severe neurological deficits. 3. Higher recurrence rate. 4.AQP4 antibody positivity rate is higher. 5. The length of spinal cord involvement is longer. In view of the above characteristics, NMO patients with combined connective tissue disease need early treatment and long-term treatment: 1. High-dose hormone shock is still preferred for rapid symptom relief in the acute phase, and if the first treatment is not effective, plasma replacement or cyclophosphamide should be applied as soon as possible. In the remission period, long-term immunosuppressants are generally needed to prevent relapse.