The distribution of parasitoids of the greenbug, Schizaphis graminum (Rondani), and corn leaf aphid, Rhopalosiphum maidis (Fitch), on sorghum in Oklahoma was studied during the summer, 1972. Parasitoids of the families Braconidae, Eulophidae, Pteromalidae, Encyrtidae, and Cynipidae, were collected. Predators were observed from the families Coccinellidae, Chrysopidae, and Syrphidae. Lysiphlebus testaccipes (Cresson) was the most abundant primary parasitoid collected from greenbugs. The predominant primary parasitoid emerging from parasitized corn leaf aphids was Aphelinus nigritus (Howard). A. varipes (Forester), an introduced primary parasitoid, was recovered from corn leaf aphids. The most abundant secondary parasitoid was Pachyneuron siphonophorae (Ashmead). Other secondary parasitoids were Aphidencyrtus aphidivorus (Mayr), Charips sp., and Asaphes lucens (Provancher). Both primary parasitoids and predators were active early in July. Secondary parasitoids were dominant by the latter half of July on parasitoids of the greenbug. The largest parasitoid populations were in the SW, followed by the Panhandle and north-central NE regions.