The main objective of this study was to examine the independent contributions of mental hardiness, social support of superiors, colleagues and partners, and stress resilience in explaining two dimensions of professional burnout (detachment and exhaustion) after controlling basic sociodemographic and some work characteristics. Given the current research, it is expected that all three predictors will have a significant contribution to the explanation of professional burnout, more specifically that individuals with higher levels of mental strength, social support from the three mentioned sources and stress resilience will have less burnout rates. A total of 1751 Croatian employees participated in the study, out of which 315 men and 1436 women. The range of age was between 17 and 65 years, while the average age of employees in the entire sample was 35 years (M = 35.22, SD = 9.2). The obtained results are consistent with expectations that employees with less mental strength, poorer social support of their supervisor and colleagues, and less resilience to stress are more detached and exhausted. The exception is the result of the social support of a partner which has not been predictive in the explanation of professional burnout. In addition, the results have shown significant contributions to some sociodemographic and working characteristics in explaining the dimensions of burnout. So, in terms of detachment, significant contributions had the sector and the level of wages, showing that public sector employees and employees with average and above average wages were less detached than employees in the private sector and employees with underpayment. In terms of exhaustion, significant gender and work hours contributions have been obtained, with higher levels of exhaustion experienced by women and employees with higher number of working hours.