Abstract: Objective:To investigate the correlation between the serum level of aquaporin 4-antibody(AQP4-IgG) and the clinical feature in patients with neuromyelitis optica spectrum disorders(NMOSD).Methods:The score of the expanded disability status scale(EDSS) and serum levels of AQP4-IgG detected by indirect immunofluorescence assay in 38 NMOSD cases were investigated.The correlations between serum level of AQP4-IgG,clinical symptom,image manifestation were analyzed.Results:The positive AQP4-IgG antibody in 23 cases(60.5%) and AQP4-IgG negative antibody in 15 cases(39.5%) were identified,and the EDSS score in positive group was significantly higher than that in negative group(P<0.05).Spearman correlation analysis showed that the serum level of AQP4-IgG antibody was positive correlation with the EDSS score and lesion segment of spinal cord(P<0.01).Three cases recurred in positive group,and no case recurred in negative group.Conclusions:The nerve impairment in NMOSD patients with AQP4-IgG antibody positive is severe.The higher the antibody and more spinal cord lesion are,the poorer the prognosis is.The patient with AQP4-IgG antibody negative is easy to recur.