Aim:
The aim is to determine the causes and consequences of combat stress in armed conflict participants.

Material and methods:
The research involved 109 service members (under 30) who participated in the russian-Ukrainian war in 2022-2024 on a rotational basis for different durations (from 4 to 18 months). Research methods included theoretical analysis and generalization of literary sources, interviews, questionnaires, and statistical methods.

Results:
The causes of combat stress in service members participating in military operations have been identified. It has been established that during the first rotation, service members most often suffer from being in conditions of constant threats (71.6 %), experience fear of death and injury (70.6 %), fear of killing a person (67.9 %), loud sounds (63.3 %) and lack of sleep (52.3 %). With the acquisition of combat experience, the frequency of these factors decreases. The research revealed the consequences of combat stress, which worsen depending on the duration of stay in a combat situation: increased aggressiveness (71.1 %), anxiety, fear (68.4 %), sleep problems (31.6 %), cognitive impairment (28.9 %), and psychosomatic disorders (26.3 %).

Conclusions:
Ensuring military personnel’s access to qualified psychological assistance, creating a support and rehabilitation program, and raising public awareness of the problems faced by service members participating in combat operations will reduce the negative effects of combat stress and help improve the quality of life of military personnel and their families.