Diaphoreolis viridis is a species of sea slug, an aeolid nudibranch, a marine gastropod mollusk in the family Trinchesiidae.

[2] This species was described from Ballaugh, Isle of Man in the Irish Sea.

[3] It has been reported in the northeast Atlantic, from Greenland and Iceland south to Roscoff, France.

[4] The maximum recorded length is 19 mm.

Found in shallow exposed and semi-sheltered rocky areas to 100 m depth.