Buellia magaliesbergensis is a species of crustose lichen in the family Caliciaceae.

Found in South Africa, it was formally described as a new species in 2021 by lichenologists John Alan Elix and Helmut Mayrhofer.

The type specimen was collected in the Magaliesberg Range (Orange Free State) at an altitude of 1,720 m (5,640 ft).

The species epithet refers to the type locality, the only location where the lichen has been documented.

The results of standard chemical spot tests are thallus K+ (yellow), P+ (yellow-orange), and C−.