Moths are known to be the primary prey of the Ozark big-eared bat (Corynorhinus townsendii ingens); however, data do not exist as to which species, families, and sizes of moths are eaten. We investigated patterns of prey consumption of C. t. ingens from 2003 to 2005 by collecting discarded moth wings and other insect parts beneath roosts in three maternity areas: north-central Arkansas, northwest Arkansas, and northeast Oklahoma. A total of 42 visits to roosts resulted in 579 remnants of insect prey representing eight insect orders. Of the discarded remains, 57.2% (n = 331) were Lepidoptera, with 81.3% (n = 269) of these identified beyond the ordinal level. Moths representing eight families and 49 species were eaten by C. t. ingens. Noctuidae was the most common family occurring in the diet with 25 species represented. Noctuidae and Notodontidae were typical prey of C. t. ingens in all areas, but consumption of other moth families varied. Corynorhinus t. ingens preyed upon a limited size range of moths, consistent with data for Corynorhinus in other locations in eastern North America. Our data increase the number of species (n = 31), genera (n = 27), and families (n = 3) of moths known to be eaten by Corynorhinus. Because two of the new families of moths documented as prey of Corynorhinus were discovered beneath feeding roosts in Oklahoma on the western edge of our study, we suggest additional surveys are needed at feeding roosts of Corynorhinus in western North America to fully understand the diets of Corynorhinus.