Background: This study aimed to analyze the relationship between the level of professional burnout, professional functioning styles, and occupational activity in a group of soldiers and civilian employees working in the military. The theoretical basis was the model of professional burnout of Christine Maslach and the concept of professional functioning styles developed by Barbara Mróz. Material and Methods: The study employed the following tools: Christine Maslach’s Maslach Burnout Inventory (MBI) to measure burnout, Barbara Mróz’s new, original Professional Functioning Scale (Skala funkcjonowania zawodowego – SFZ) in occupational psychology, and a questionnaire assessing the level of occupational activity. Results: The results of statistical analyses showed statistically significant differences between soldiers and civilian employees in selected dimensions of burnout (depersonalization t = 3.723, p < 0.001) and professional functioning styles (authoritarian t = 5.031, p < 0.001; avoidant t = –3.153, p < 0.002; cooperative t = –4.531, p < 0.001). All differences were higher among soldiers. Occupational activity proved to be a statistically significant factor differentiating operational effectiveness and stress resistance (t = –4.934, p < 0.001). Here, the difference was higher among military personnel. Correlations were found between professional functioning styles and burnout levels (authoritarian and avoidant styles were associated with higher burnout levels, the cooperative style had a protective effect). Soldiers: correlation positive (r = 0.270, p < 0.05), prefer an authoritarian style – based on control, decision-making, and hierarchy. Civilian employees: correlation positive (r = 0.377, p < 0.01), that the more often used an authoritarian style in their professional functioning, the higher their overall level of burnout was. Conclusions: The results obtained are relevant for human resource management in military organizations and for the development of psychological support programs and training in coping with stress and developing effective professional functioning styles. Med Pr Work Health Saf. 2026;77(2)