Medicinal plants are an important component of local plant diversity. Their study is of high scientific and practical significance, related to the conservation and sustainable use of their resources. The present study presents results of the inventory of medicinal plants on the territory of the Petrohan Training and Experimental Forest Range (Western Stara Planina, Bulgaria). A total of 140 species of medicinal vascular plants belonging to 113 genera and 53 families were recorded. The systematic structure of the studied plants is characterized and the classification of plant species according to biological type, life form and geoelement is presented. The information on the usable parts of the medicinal plants and the biologically active substances contained as well as medicinal action are presented. Specifying species composition and resource status will contribute to assessment of medicinal plants as an ecosystem service offered by forest communities. A list of medicinal plants on the territory of the Petrohan Training and Experimental Forest Range is presented, too.