Lethariella sinensis is a species of fruticose lichen in the family Parmeliaceae. It was formally described as a new species in 1982 by Chinese lichenologists Jiang-Chun Wei and Yu-Mei Jiang. The type specimen was collected from Qamdo (eastern Tibet) at an altitude of 4300m (14,100feet); there, it was found growing on the branch of Thuja. It is an orange, long lichen with a surface. In 2001, Walter Obermayer showed that the holotype specimen of Lethariella sinensis comprised two chemically unique taxa: one with psoromic acid and the other with norstictic acid. The former was chosen as the lectotype, and as a consequence, Lethariella mieheana became synonymous with L. sinensis.
Lethariella sinensis is one of three species of Lethariella that is used as a purported health-promoting tea in Yunnan, China. Thin-layer chromatography analysis shows the presence of the following lichen products in the thallus: atranorin, canarione, psoromic acid, 2'-O-demethylpsoromic acid, and traces of gyrophoric acid.