Based on morphological and phylogenetic analyses, during a study on the biodiversity of the lichenized fungi family Arthoniaceae in Yunnan, China, three new species of Arthonia, Eremothecella, and Synarthonia (Arthonia yunnanensis sp. nov., A. pararubella sp. nov., Eremothecella pruinocarpa sp. nov.) and three new Chinese records (A. rubella, E. calamicola, Synarthonia inconspicua) were reported in this present study. A phylogenetic analysis using maximum likelihood and Bayesian inference based on a two-gene dataset (mtSSU and RPB2) revealed that all these species form distinct independent clades. In addition, this study represents the first report of molecular sequences for the genus Eremothecella. Detailed descriptions, ecological and chemical characteristics, and illustrations for each species are provided. Keywords: lichenized fungi; morphology; phylogeny; taxonomy.