Ocellularia peremergens is a species of corticolous (bark-dwelling) lichen in the family Graphidaceae.

Found in Thailand, it was formally described as a new species in 2002 by lichenologists Natsurang Homchantara and Brian J. Coppins.

The type specimen was collected from Doi Inthanon National Park (Chiang Mai Province) at an elevation of 2,450 m (8,040 ft).

The lichen has a shiny, pale greenish-grey thallus with a finely verruculose (warted) texture and a white medulla.

The apothecia occur solitarily, measuring 0.7–1.2 mm in diameter; they are emergent, meaning they project somewhat above the thallus surface.