To explore the relationship between job burnout and cognitive function and the influencing factors of job burnout among medical staff. Questionnaire survey was conducted for 197 medical workers in a grade-three general hospital in Beijing. Maslach Burnout Inventory-General Survey (MBI-GS) was carried out to assess the degree of job burnout among medical staff; Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was used to evaluate the overall cognitive function and cognitive situations of different dimensions. (1) There was a certain level of job burnout among medical staff, especially for the emotional exhaustion dimension (13.29 ± 7.67). (2) High level job burnout group (81.08 ± 12.34) scored lower on visual span than low level job burnout group (92.48 ± 19.62), P<0.05. Overall, job burnout had a negative influence on the general cognitive function (P<0.05). (3) The results of regression analysis indicated that, inefficacy was negatively correlated with age (r=-0.162, P<0.05). Job burnout was positively correlated with level of education (r=0.234, P<0.05) as well as exercise frequency (r=0.320, P< 0.001), and emotional exhaustion was correlated with overtime work (r=0.135, P<0.05); Level of job burnout stayed higher among doctors and nurses, compared with administration staff in hospitals (t=2.966, P<0.05). Job burnout of medical staff was relatively in high level; influenced by age, education level, overtime work, exercise frequency and occupational type, job burnout affected the visual span and general cognitive function.