Objective To determine clinical characteristics associated with fatigue in patients with neuromyelitis optica (NMO). Methods A questionnaire survey was conducted in NMO patients, measuring fatigue using the fatigue impact scale (FIS). Results A total of 64 NMO patients (mean age: 50.0 years; male/female: 3/61) completed the survey: 71.9% were NMO-IgG seropositive and 43 (67.2%) received immunosuppressive treatments. The patients obtained a global FIS score of 64.8±36.1, with 13.2±8.5, 20.6±11.6 and 31.0±18.7 for the cognitive, physical and social dimensions, respectively. No significant differences were found in global FIS scores ( P=0.294 9), and cognitive ( P=0.467 1), physical ( P=0.472 2) and social ( P=0.212 6) dimensional scores between those with and without immunosuppressive treatments. Age, sex, serum NMO-IgG, duration of disease and annual relapse rates were neither correlated with global FIS scores ( P>0.05), nor with the three dimensional scores ( P>0.05). The Expanded Disability Status Scale score was positively associated with global FIS scores ( P=0.000 5)and cognitive( P=0.018 7), physical( P=0.000 4) and social ( P=0.000 5)dimensional scores. The frequency of attack was also positively correlated with cognitive dimensional scores ( P=0.007 9).Conclusion Disability is associated with cognitive, physical and social dimensions of fatigue. High frequency of attack is positively correlated with the cognitive dimension of fatigues.