Data were collected to investigate effects of deltamethrin and fipronil on ectoparasites from black-tailed prairie dogs in South Dakota, USA. In late-July 2018, we treated 3 sites with 0.05% deltamethrin dust and 5 sites with host-fed 0.005% fipronil grain. Three non-treated sites functioned as experimental baselines. We collected ectoparasites before treatments (June-July 2018) and after treatments (August-October 2018, June-July 2019). We combed ectoparasites from live-trapped, anesthetized prairie dogs. Trapping on treated and non-treated sites occurred simultaneously or nearly simultaneously in each year. Detected ectoparasites were counted and placed back on the prairie dogs from which they were collected to reduce a removal effect. Ectoparasites included fleas, lice, and mites.