Konza Prairie Biological Station is a native tallgrass prairie preserve in Riley and deary Counties. Kansas, where seventy-eight species of butterflies (Lepidoptera) were collected or sighted from 1997 through 1999. Basedon known larva] hosts, 65% were from prairie or open field habitats with 24% grass feeders, 25% from woodland or woodland borders and approximately 10% from mixed or unknown habitats. There were 1I new records for Riley County: Northern Cloudy Wing, Thorybes pylades (Scudder) (Hesperiidae), Funeral Dusky Wing, Erynnis funeralis (Scudder & Burgess) (Hesperiidae), Little Glassywing, Pompeius verna (W. Edwards) (Hesperiidae), Byssus Skipper, Problema byssus kumskaka (Scudder) (Hesperiidae), Hobomok Skipper, Poanes hobomok (T. Harris) (Hesperiidae), Dusted Skipper, Atrytonopsis hianna turneri H. A. Freeman (Hesperiidae), Coral Hairstreak, Harkenclenus titus (Fabricius) (Lycaenidae), Banded Hairstreak, Satyrium calanus falacer (Godart) (Lycaenidae) and Hickory Hairstreak, Satyrium caryaevorum (McDunnough) (Lycaenidae), Summer Azure, Celastrina neglecta (W. Edwards) (Lycaenidae) and Northern Pearly Eye. Enodia anthedon A. H. Clark (Satyridae). The larvae of Reakirt's Blue, Hemiargus isola ah-e (W. Edwards) (Lycaenidae) were found feeding on the flowers of Catclaw Sensitive Briar, Shrankia nuttallii (DC.) Standl. (Mimosaceae), a new host record A checklist is given for species found during the survey period and those whose host, habitat or distribution make it likely they may be found on Konza Prairie in the future.