ABSTRACT. Background. Complex severe wounds require enormous efforts in their treatment. Negative pressure wound therapy, or vacuum assistance wound closure (VAC), is a promising method of accelerated wound healing. However, its efficacy needs to be approved and explained. Objective. Histological, immunohistochemical and electron microscopy assessment of wound healing under negative pressure comparing with conventional wound cure. Methods. Histological, immunohistochemical, electron microscopy and morphometric evaluation of specimens from wound bed at admission of patients, 3 and 7 days of treatment. The morphometric analysis was performed using the ImageJ image analysis software. Results. Morphological evaluation demonstrated reduction of inflammatory infiltration, advance in wound re-epithelisation and support of negative pressure wound therapy in collagen matrix remodeling due to early proliferation of fibroblasts, elevated collagen production and myofibroblasts differentiation. Immunohistochemical labeling of vascular endothelial marker CD34 revealed significantly enhanced angiogenesis in the wound that occurs as formation of more developed and functioning microvessels on day 3 of negative pressure wound therapy comparing to control group and its reduction on 7 day of treatment. Conclusion. Vacuum assistance wound closure is a more effective method of severe combat wounds healing, than application of gauze bandages. Negative pressure wound therapy benefits a wound repair by enhancing angiogenesis, diminishing inflammation, and contributing to early connective tissue development.