An extensive research has been performed to investigate the mechanisms of action by which the application of subatmospheric pressure to wounds increases the rate of healing. Increased blood flow with vacuum-assisted closure (VAC) use is the most popular aspect. Fibronectin, which is an adhesion molecule, has several functional domains mediating chemotaxis, adhesion and migration. This is thereby involved in differentiation, proliferation, inflammation and thus in wound healing. In this study, plasma fibronectin levels were measured before and after VAC in patients with wounds. The results showed that there was an increase in pre- and post-VAC levels of plasma fibronectin. This statistically significant increase could be another explanation of how VAC therapy promotes wound healing.