This paper presents the results of a combined analysis of 300 specimens of the genus Cladonia collected in the southwest of province of Pontevedra. The species were classified based on to morphological, chemical (TLC) and genetic (ITS rDNA) characters. A total of 28 species were identified, including is the first record for the Iberian Peninsula of Cladonia portentosa, which contains fumarprotocetraric, perlatolic and usnic acids, as well as Cladonia homosekikaica, new for the Galician flora and Cladonia ciliata, a new record for the province of Pontevedra. It is important to note that morphological characteristics, chemistry and DNA sequences are essential in the taxonomy of the genus.