Goniobranchus aureomarginatus is a species of colourful sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Chromodorididae.
This chromodorid nudibranch has a white mantle which is edged with yellow. The rhinophores and gills are translucent white with some opaque white pigment on the gill rachis and the rhinophore lamellae.
This species was described from Auckland harbour and Waiwera, New Zealand. It is apparently a New Zealand endemic.