An inventory of 273 lichens and allied fungi (including 19 lichenicolous and 6 non-lichenized saprobic calicioid fungi) of Žemaitija National Park (Lithuania) is presented. Geography, climate, vegetation and anthropogenic activities in the Park are described briefly. Nine species are reported for the first time in Lithuania: Chaenotheca brunneola, C. gracillima, Cliostomum corrugatum, Lecanora circumborealis, Microcalicium ahlneri, Pycnora praestabilis, Thelocarpon impressellum, Trapelia corticola and Tremella lichenicola. Cresporhaphis pinicola is reported for the first time outside Southern and Central Europe. Key words: Lichens, biodiversity.