Doto millbayana is a species of sea slug, a nudibranch, a marine gastropod mollusc in the family Dotidae.

It has subsequently been reported widely in Britain and Ireland, and south to Galicia, Spain.

[2] This nudibranch is translucent white with dark red spots on the ceratal tubercles.

The back and sides are spattered with red pigment which extends up the inner faces of the rhinophore sheaths.

[3] Doto millbayana feeds on the hydroid Plumularia setacea, family Plumulariidae.