The study of acoustic signals from various representatives of insects, and in particular coleopterans, has a long history. In the Russian-language literature, systematic, faunistic and ecological studies on aquatic beetles, including those on the family Hydrophilidae, are widely known; however, studies on the bioacoustics of the coleopteran group are quite rare. The aim of our study was to study stress signals of two species of Hydrophilidae – Berosus frontifoveatus Kuwert, 1888 and Berosus spinosus Steven, 1808.