Phyllidiopsis krempfi is a species of sea slug, a dorid nudibranch, a shell-less marine gastropod mollusk in the family Phyllidiidae.

[2] This species was named to honour Armand Krempf, a French marine biologist and director of the Nha Trang Institute of Oceanography (Vietnam) from 1921.

[3] This nudibranch has a white or pink dorsum with compound tubercles with white apices.

It is a large Phyllidiid, growing to at least 60 mm in length.

It is similar to Phyllidiopsis pipeki but that species has only two longitudinal black lines on the back.