Bats appear regularly among the mammalian prey species of the barn owl. However, from numerous studies of owl pellets, bats are rarely represented in the prey of the barn owl and usually make up less than 1% of the prey individuals. Prey remains of the barn owl from the fortress Dömitz, south-east of Mecklenburg-Western Pomerania (Germany) were collected and analysed. A total of 2931 identifiable fragments from at least 1100 vertebrate individuals were discovered and identified. The analysis of the pellets over a four year period shows that, aside from the typical spectrum of mammalian prey (voles 34.9%, shrews 24.6 % and mice 13.8%), a relatively large proportion of prey individuals (26.6 %) were bats. From the pellet sample from 2002, Natterer’s bat Myotis nattereri were clearly the dominant prey with 79 individuals (30.2 %) followed by the common vole Microtus arvalis with 74 individuals (28.2 %). This high frequency of bats from the 2002 sample led to a total percentage of bats of almost 39 % and bats were clearly dominant over other potential prey groups. The frequency of bats in all samples is much higher than in all other known studies of barn owl pellet samples in a comparable volume. Our results show that Tyto alba is an opportunistic but no selective hunter of bats.