Asplenium ascensionis is a species of fern in the family Aspleniaceae that is endemic to Ascension Island.

A. ascensionis is endemic to central Ascension Island in the South Atlantic Ocean, where it grows on Green Mountain and the surrounding areas at altitudes of 430–770 m (1,410–2,530 ft) above sea level.

[2] The fronds measure 3–6 in (76–152 mm) long with 15-25 irregularly-shaped pinnae on each side.

[3] Adult A. ascensionis plants are capable of reproducing vegetatively, with small plantlets growing from the tips of the fronds, or sexually, with spores that are dispersed by the wind.

Spores seem to require damp, shaded conditions to germinate, with most young plants and gametophytes occurring in sheltered crevices.