The subject of this master thesis is the lichen flora of relict pine forests with Pinus sylvestris in southern and western Bohemia (PLA and NP Šumava) in the basin of the river Otava in mesofytic and oreofytic zone. The first part of my thesis consists of interesting and problematic taxa description. Statistical analyses and evaluation of environmental parameters influence are discussed in the second part of this work. In past decades lichens of Scots pine forests have often been studied but coherent classification is still missing. Up to 260 species of lichens and lichenicolous fungi were found in literary sources. In my own work I reffered 229 species, several of them not mentioned in examined publications. Two of these species are new in the area of the Czech Republic – Rhizocarpon drepanodes and Rhizocarpon superficiale. Two criticaly endangered species (Cladonia stellaris and Hertelidea botryosa) were discovered together with Cladonia decorticata that was considered to be extinct. The number of recorded lichens represents about 15 % of the known lichen flora of the Czech Republic (Liška et al. 2008). Several species sensitive to the environment weren’t confirmed in localities in this study; especially epiphytic lichens (e.g. Bryoria bicolor, B. implexa, Bunodophoron melanocarpum, Evernia divaricata, E. mesomorpha, Hypogymnia vittata, Sphaerophorus globosus and Usnea florida). Some terricolous lichens weren’t found too (Cetraria ericetorum, Cladonia crispata, C. scabriuscula and C. zopfii). Most of these species are rare within the Czech Republic. The analysis of environmental parameters influencing on species diversity revealed that the altitude is the only significant environmental variable. The best correlating species with this variable are Hypogymnia farinacea, Protoparmelia badia and Vulpicida pinastri. On the other hand, Lassalia pustulata, Ramalina pollinaria, Tuckermannopsis chlorophylla, Xanthoparmelia stenophylla, X. verruculifera and Cladonia polydactyla are negatively correlating with altitude.