A total of 205 lichen taxa (198 species, 2 subspecies, 4 varieties, I forma) and one lichenicolous fungus were identified from 25 different localities in the Batman, Mardin, Osmaniye and Sivas regions of Turkey. Cladonia metacorallifera, Caloplaca flavocitrina, Caloplaca variabilis f, ocellulata, Phaeophyscia chloantha. and Usnea wasmuthii are new to Turkey. 130 species and one lichenicolous fungus (Lichenodiplis lecanorae) are new records from Osmaniye. Moreover, 50 taxa are reported as new from Mardin, 35 from Sivas, and 23 from Batman. Distribution and substrata are summarized for the complete annotated species list posted at http://www.mycotaxon.com/resources/weblists.html.