Objectives: We aimed to investigate the prevalence of burnout among medical oncology physicians and the relevantfactors on a large scale in Turkey. Methods: A total of 285 medical oncology physicians participated the study. Two forms were used to define sociode mographic and professional characteristics and Maslach burnout inventory was used to measure burnout levels. Logis tic regression analyses were performed to determine the factors affecting burnout. Results: Emotional exhaustion was observed in 37.5% of the participants. Emotional exhaustion was significantly high er in females (p=0.004), younger physicians (p=0.012), those without children (p<0.001), research assistants (p<0.001),those with less than 3 years of professional experience (p=0.022), those who work 40 hours and above per week(p=0.022), those with a monthly income less than $1.200 (p=0.003), those without a hobby (p: 0.001), and those whodo not exercise regularly (p=0.001). In the multivariate analysis, not having any hobbies (p=0.01) and working morethan 40 hours a week (p=0.003) were the significant factors affecting emotional exhaustion. Conclusion: In this study, the factors affecting burnout were increased weekly working hours and not having any hob bies. Measures to reduce burnout in medical oncology physicians should be considered both on an organizational andpersonal basis.