Diolcogaster is a genus of parasitoid wasps within the subfamily Microgastrinae of the family Braconidae. The genus is poorly studied, likely with multiple undescribed species.[1][2] The type species is Diolcogaster melligaster (Provancher, 1886), formerly Microgaster melligaster.[3] Species in this genus parasitize lepidopterans and are geographically widespread. There are more than 140 described species in Diolcogaster found throughout the world.[3][4]