The paper presents a list of 94 species of lichens found in central part of the Landscape Park “Podlasie Bug Water Gap”. Among them, 16 species are endangered in Poland. The most valuable components biota of lichen belong to endangered species nationally. They are: Melanelixia subargentifera, Pleurosticta acetabulum, Ramalina fraxinea, Usnea filipendula and others.