Objectives To study the general clinical characteristics of the neuromyelitis eptica spectrum disorders（ NMOSD） and the difference from multiple sclerosis（ MS）. Methods Patients with central nervous system demyelinating diseases admitted to the Neurology Department of Xuanwu Hospital from January 2016 to December 2017 were screened according to the diagnostic criteria of NMOSD（ 2015） and the diagnostic criteria of McDonald（ 2017）. A retrospective analysis was conducted to compare the clinical features of NMOSD and MS patients. Results Totals of 233 NMOSD patients and 125 MS patients were induded. The average onset age of NMOSD and MS were（ 43.0±14.7） and（ 38.1±11.2） years respectively， and the male to female ratio was（ 1/4.5） and（ 1/2.6）. NMOSD mostly begin with the optic nerve damage symptom. Intractable pruritus and intractable nausea and vomiting may be characteristic clinical features. The MS mostly begin with brain damage. Most NMOSD and MS patients have no obvious causes of first onset. Possible causes are upper respiratory tract infection， fatigue， vaccination， postpartum and so on. There was no significant difference between NMOSD and MS in cerebrospinal fluid pressure. Compared with MS patients， NMOSD patients has higher white blood cell count than normal.Blood AQP4-Ab and cerebrospinal fluid OB were important biomarkers to distinguish from the two diseases. Conclusions NMOSD is the most likely to be misdiagnosed as MS， especially in the early stage of the disease and NMOSD patients with negative AQP-4 antibody test. Intractable itching and intractable nausea and vomiting may be underestimated features of NMOSD. Blood AQP4-Ab and cerebrospinal fluid OB are important biomarkers of NMOSD and MS， which are significant for the identification of the two diseases.