Herpothallon subglobosum is a species of corticolous (bark-dwelling), crustose lichen in the family Arthoniaceae.

Found in China, it was formally described as a new species in 2022 by Pengfei Chen and Lulu Zhang.

The type was collected in Baimaluo (Weixi County, Yunnan) at an elevation of 2,100 m (6,900 ft).

The lichen contains gyrophoric acid, lecanoric acid, and umbilicaric acid, which are lichen products that can be detected using thin-layer chromatography.

The species epithet subglobosum refers to the somewhat spherical pseudisidia.