Primary systemic vasculitis comprise a group of diseases such as Wegener's granulomatosis, Kawasaki disease, Takayasu arteritis, giant cell arteritis with various clinical manifestations, and an etiology not fully understood. The pathogenesis involves an inflammatory infiltration of the vessel wall, which results in its damage. Matrix metalloproteinases seem to participate not only in the degradation of structural components of a vessel wall which leads to bleeding and/or aneurysmal dilatation. In addition, they play a significant role in the in inflammatory cells migration and development of inflammatory infiltration. This process, and the proliferation and migration of smooth muscle cells may result in the narrowing of the affected vessels. This article outlines the role of matrix metalloproteinases in primary systemic vasculitis.