Burnout syndrome is a growing problem for both employees and organisations whose severity depends on demands and resources in the environment. More specifically, individuals with more resources, such as social support, are less susceptible to work overload in comparison to those with reduced resources, according to Theory of conservation of resources (COR). However, not all individuals are equally affected by their environment. The effect size of the environment is largely influenced by individual's personal characteristics as well, such as work motivation. Self-determined motivation, caused by the satisfaction one gets from performing the activity itself, is associated with reduced possibility of experiencing work related burnout. It can function as an individual characteristic which the effect size of environmental resources, such as social support at and outside of workplace, on individual depends on. Hence, the aim of this study is to investigate the moderating effect of self-determined work motivation on a relationship between social support and work-related burnout. The study involved 483 participants. The Multidimensional Work Motivation Scale (MWMS) was used to measure the self-determined motivation, Burnout Assessment Tool (BAT) for measuring work-related burnout, while social support was measured by the Multidimensional Scale of Perceived Social Support (MSPSS) and Job Demands-Resources Questionnaire. The results showed insignificant effect of self-determined work motivation on relationship between perceived social support and level of work-related burnout, regardless of the type of social support. Results deviate from previous research that reported similar moderating effects, presumably due to differences in population and used measures. Hence, further research of the effect in question is needed.