Notaeolidia gigas is a species of sea slug, an aeolid nudibranch, a marine gastropod mollusc in the family Notaeolidiidae.
The species was first described in 1905 based on collections from the South Orkney Islands and was later redescribed in 1990 based on a specimen collected from King George Island. It has been reported from a number of Antarctic localities at depths of 3âÂÂ50 m.