Baeolidia harrietae is a species of sea slug, an aeolid nudibranch. It is a marine gastropod mollusc in the family Aeolidiidae.
This species was described from the Great Barrier Reef, Australia. It has been reported from Papua New Guinea, the Philippines and the Ryukyu Islands, Japan.
Baeolidia harrietae is an extremely flattened animal which hides on the surface of the colonial zoantharian Palythoa.