Objective: To investigate the level and influencing factors of job burnout among nurses in tumor hospital. Methods: A total of 240 clinical nurses from specialized cancer hospital in Tianjin were investigated with a self-designed general information questionnaire and Chinese version of Maslach burnout inventory. Results: The incidence of job burnout among nurses was 65%, the score of emotional exhaustion dimension was（20.21 ±10.08）, the score of depersonalization dimension was（5.74±5.32），the score of achievement dimension was（32.10±10.51）. Logistic regression analysis showed that the possibility of job burnout improving one grade or more among nurses with more night shift, was 2.98 times than those nurses with no difference between night shift and day shift; Besides, the possibility of job burnout improving one grade or more among nurses older than 30, was 1.77 times younger than 30. Conclusion: The level of job burnout among oncology specialized nurses is mild to moderate, more attention should be paid to young nurses with more night shift, and individual interventions should be designed and performed for them.