Felimare cantabrica is a species of colourful sea slug or dorid nudibranch, a marine gastropod mollusc in the family Chromodorididae.
Felimare cantabrica has a light and dark blue body, flecked with yellow lines and spots. Its mantle edge is lined with yellow-light blue-yellow banding. The gills and rhinophores are purple.
This species can reach a total length of at least 40 mm and has been observed feeding on sponges from the genus Dysidea.