This dataset contains 4 separate data files: (1) "Hawaiian Islands, genetic metabarcoding of Hawaiian hoary bat guano samples, 2010-2021" - sampling details for guano collected from Hawaiian hoary bats (Lasiurus semotus) on the Island of Hawai‘i, O‘ahu, Maui, and Kaua‘i, which was used in a dietary metabarcoding study; (2) "Hawaiian Islands, Hawaiian hoary bat guano representative DNA sequences to family level, 2010-2021" - list of the unique sequences identified in the bat diet that were identified to arthropod family using genetic methods; (3) "Island of Hawai‘i and Maui, bat diet insect DNA barcode reference library, 2016-2020" - sampling details for the insect reference library and associated genetic barcodes; (4) "Island of Hawai‘i, genetic identification of caterpillars collected and reared from host plants, 2020" - sampling details for caterpillars collected from host plants, which were identified to family using genetic methods.