The genus Diglyphomorphomyia Girault is newly reported from the Neotropical region, with the majority of material and species from Costa Rica. It is represented by nine species in the region, and all are new species described here: D. albiclava, D. albicoxa, D. carinifer, D. costulata, D. cristata, D. metallica, D. parva, D. pedunculata, D. pilosa. An identification key for the species is included. The Neotropical species of this genus differ in one morphological feature from Old World species, but share several important characters with the type species of Diglyphomorphomyia from Australia. The biology of Diglyphomorphomyia species is unknown, but they are probably parasitoids of concealed lepidopteran larvae.