During a survey of fungi on Rhododendron in China, Lecanora rhododendri sp. nov., was identified. In this paper, it is introduced with a detailed morphological description and illustrations. The species' novelty is justified on the basis of its distinct morphological characteristics and phylogenetic analyses of a concatenated internal transcribed spacer (ITS) and mitochondrial small subunit (mtSSU) sequence data using maximum likelihood and maximum parsimony criteria, as well as ITS and mtSSU nucleotide base comparisons with related taxa. A preliminary chemical test with 5% KOH and Lugol's reagent on the thallus, apothecial margin, and asci was also observed. The fungus was collected from dead branches of Rhododendron sp. in Yunnan, China. In the phylogenetic analyses of a combined ITS and mtSSU sequence dataset, the species formed a separate branch and has a close relationship with Lecanora orientoafricana in the genus Lecanora (Lecanoraceae, Lecanorales). Morphologically, the new isolate is typical of Lecanora in having a crustose thallus; apothecial, sessile ascomata with black-brown discs; Lecanora-type clavate asci; and hyaline, subglobose to obovoid aseptate ascospores. Keywords: Lecanoromycetes, Lichenized fungi, New species, Rhododendron inhabiting fungi, Taxonomy.