A positive AQP4 antibody may indicate optic neuromyelitis optica and optic neuromyelitis optica spectrum disorders. AQP4 antibody, i.e. aquaporin-4 antibody, has a high specificity and relatively high sensitivity for the diagnosis of optic neuromyelitis optica and optic neuromyelitis optica spectrum disorders, and is an indispensable adjunctive test for clinical diagnosis of optic neuromyelitis optica and optic neuromyelitis optica spectrum disorders, and the test result for a normal person should be negative. A positive AQP4 antibody does not directly confirm the diagnosis of optic neuromyelitis optica and optic neuromyelitis optica spectrum disorders. In addition, a comprehensive analysis of the patient’s clinical symptoms, medical history, signs and symptoms, as well as other ancillary tests, and the gradual exclusion of other diseases, are required to make a definitive diagnosis. Laboratory test results should be interpreted by a medical professional, and patients with positive AQP4 antibodies are advised to go to neurology, ophthalmology, and other related departments in regular hospitals for detailed consultation.