Three species of robber flies (Asilidae) are recorded as preying on workers of Pogonomyrmex harvester ants in eastern New Mexico and western Texas: Cerotainiops abdominalis, Saropogon combustus, and Saropogon pritchardi. Of 379 prey records for C. abdominalis, 66% were Pogonomyrmex workers. Two species of Saropogon were collected in association with a large number of harvester ant workers: S. combustus (40% of 263 prey records) and S. pritchardi (94% of 288 prey records). All three species show a statistical preference for Hymenoptera, specifically for harvester ant workers, and avoidance of Diptera, Hemiptera, Lepidoptera, and Orthoptera prey. A brief review of invertebrate predators of Pogonomyrmex workers is given, with emphasis on asilid predators. For the three asilid predators mentioned in the article, seasonality, observed behaviors, and a list of known prey taxa are included.