The tropical areas of eastern Asia contain a high diversity of foliicolous lichens, including various species of the genus Badimia. Badimia xanthocampylidia W. C. Wang & J. C. Wei is described from tropical rainforests in southern China and Thailand based on morphology, chemistry, and combined mtSSU, ITS and nrLSU sequences. It is characterized by a pale green thallus with yellow verrucae and bright yellow campylidia and the presence of isousnic acid. Three other species, B. multiseptata Papong & Lücking, B. pallidula (Kremp.) Vězda and B. polillensis (Vain.) Vězda, are discussed and the genus Badimia is newly reported from China. A worldwide key to currently known species in the genus is presented.