During the period of full-scale war in Ukraine, the study of volunteers’ mental health has gained special importance, as they are exposed to prolonged traumatic stress. This study aimed to identify the clinical and psychodiagnostic features of neurotic and stress-related disorders in volunteers and to evaluate the effectiveness of a treatment and psychosocial correction program. A total of 288 volunteers aged 18 to 60 years participated in the study. They were divided into an experimental group, which received the "Problem Management Plus" program combined with pharmacotherapy, a control group that underwent pharmacotherapy treatment, and a reference group without mental disorders. Diagnoses were verified by the clinical-psychopathological method according to ICD-10 and the Ukrainian National Classifier of Diseases NK 025:2021. Psychodiagnostic assessment was performed using SCL-90-R (Symptom Checklist-90 Revised), HAM-D (Hamilton Depression Rating Scale), HAM-A (Hamilton Anxiety Rating Scale), and HADS (Hospital Anxiety and Depression Scale) before the program, immediately after it, and three months later. The experimental group demonstrated a significant reduction in anxiety, depression, and somatization scores, while the control group showed less pronounced changes. Three months later, the effect of the program was preserved, and the results in the experimental group did not differ from those in the reference group. These findings confirm the effectiveness of comprehensive psychosocial support programs in maintaining the mental health of volunteers under conditions of war-related stress. Further studies should focus on long-term follow-up and evaluation of different intervention formats.