The article is devoted to the results of research of the lichen biota of Azerbaijan. Based on the conducted study it's been identified 811 species out of 202 genera, 67 families and 24 orders. 28 new species and 2 subspecies. Taxonomic and ecobiomorphological features of the studied lichen biota have also been determined. Due to nomenclatural changes, the family spectrum has increased by 12 families, and the genus spectrum by 47 genera in the taxonomic structure. 166 relict and 13 rare species which need protection have been identified and entered into the Red Book of Azerbaijan: Heterodermia dactyliza (Nyl.) Swinscow et Krog, Lecanora leptyrodes (Nyl.) Nilsson, Lecanora multispora Makar, Usnea longissima Ach. Anaptychia elbursiana (Szat.) Poelt. Cladonia strepsilis (Ach.) Grognot), Ramalina Montana Barkhal, Cetraria islandica (L.) Ach. Bilimbia pulchra Oxn. Lobaria pulmonaria (L.) Hoffm. Sterecaulon alpinum Laurer, Tornabea scutellifera (With.) J. R. Laundon, Usnea florida (L.) Weber ex F. H. Wigg.).