The Bieszczady Mts, a mountain range in SE Poland, is a hot spot of fungal richness and diversity in Poland. This paper summarizes 5 years of studies in the Bieszczady Mts, as well as previously published research. A total of 1,377 macromycetes taxa were found, including many (464) which were protected, red-listed, or very rare in Poland. Thirty-eight taxa (nine Ascomycota and 29 Basidiomycota) have been reported in Poland for the first time: Agrocybe gibberosa, Auriporia aurulenta, Bolbitius variicolor, Bulgariella pulla, Chaetosphaerella phaeostroma, Clitocybe subspadicea, Clitopilus passeckerianus, Cortinarius anomalus var. subcaligatus, C. fervidus, C. flexipes var. inolens, C. sylvae-norvegicae, Cudoniella tenuispora, Entoloma bisporigerum, E. olorinum, E. poliopus var. parvisporigerum, E. sericeoides, Galerina caulocystidiata, Gymnopilus josserandii, Hymenoscyphus subferrugineus, Hypholoma olivaceotinctum, Inocybe queletii, Laccaria altaica, Lactarius romagnesii, L. rostratus, Mycena epipterygia var. atroviscosa, M. epipterygia var. candida, M. polygramma f. candida, Octavianina lutea, O. mutabilis, Pachyella violaceonigra, Panaeolus papilionaceus var. capitatocystis, Phaeocollybia jennyae, Psathyrella almerensis, Pyrenopeziza inornata, Scutellinia torrentis, Tricholoma basirubens, Tricholomopsis flammula, and Vibrissea decolorans. For all new taxa, short descriptions based on the collected material have been provided.