Cryptothecia austrocoreana is a species of crustose and corticolous (bark-dwelling) lichen in the family Arthoniaceae.

Found in South Korea, it was formally described as a new species in 2017 by Jung-Jae Woo, László Lőkös, Edit Farkas, and Jae-Seoun Hur.

The type specimen was collected by the first author near Seonamsa (Suncheon, Jeollanam Province) at an altitude of 160 m (520 ft); here it was found growing on the bark of Meliosma myriantha.

The specific epithet austrocoreana refers to the southern part of South Korea.

[1] Lichen products found in Cryptothecia austrocoreana include barbatic acid as a major constituent, minor amounts of atranorin, and trace amounts of chloroatranorin.