New and noteworthy records from lichenological fieldwork conducted in 2020 in the southeastern part of the Kaliningrad region (former Ostpreußen) are presented, mainly from Vishtynetsky Nature Park. Altogether 33 species are new to the Kaliningrad region, including Zwackhia sorediifera new to Russia. Lecidella subviridis is new to European Russia outside of the Caucasus. Twelve species, which are rare or protected in the region, are also treated. Most lichen species, also rare and threatened ones, were reported in old-growth broadleaved, mixed spruce-broadleaved, and black alder forests, as well as old-growth broadleaved alleys. In Vishtynetsky Nature Park, pine forests and bogs are also rich in lichens, including rare species and taxa which in neighbouring countries are classified as associated with forests of high conservation value. Protected sites play an important role in maintaining the natural habitats and the biodiversity of the Kaliningrad region, however, many valuable forests are still threatened by logging and deserve protection. Key words: old-growth forests, Rominten Forest, East Prussia, Baltic region.