Phacopsis vulpicidae is a species of lichenicolous (lichen-dwelling) fungus in the family Parmeliaceae.

The type specimen was collected by the first author near the headwaters of Ar Khordolyn gol River in Renchinlkhümbe Somon (Khövsgöl Province, Mongolia), at an altitude of 2,050 m (6,730 ft).

There, in the upper limit of a Larix sibirica forest, the fungus was found growing on the thallus of a ground-dwelling Vulpicida juniperina lichen.

Infections by the fungus cause blister-like (bullate) swellings of the host thallus.

It is known to occur in arctic and mountain tundra and taiga biomes of Asia, Europe, and North America (Alaska).