Acheilognathus deignani is a species of freshwater ray-finned fish in the genus Acheilognathus.

It is endemic to northern Vietnam in the Mekong River.

It grows to a maximum length of 5.2 cm.

Named in honor of Herbert Girton Deignan (1906-1968), Associate Curator of Birds, U.S. National Museum, who collected the type specimen.

This Acheilognathinae article is a stub.