Pertusaria hypostictica is a species of corticolous (bark-dwelling), crustose lichen in the family Pertusariaceae. Found in Thailand, it was formally described as a new species in 2005 by Sureeporn Jariangprasert. The type specimen was collected from Khao Yai National Park (Nakhon Ratchasima province) at an altitude of , where it was found growing on the bark of a Fagaceae plant. It has also been found in the peninsular region in the southern part of Thailand. The species epithet refers to the presence of hypostictic acid as a minor lichen product. It also contains stictic acid as a major substance, minor amounts of cryptostictic acid, peristictic acid, substictic acid, and trace amounts of constictic acid.