The Kampinos Forest is a forest complex located in the central part of Masovian Lowland. Its present area is a remnant of vast primeval forests that covered Masovia in the past, and at present almost its entire area is under protection as the Kampinos National Park. This park is the second largest and the only national park in Central Poland, but terrestrial true bugs occurring there have never been the subject of comprehensive research. In literature, we can find informations about only a few dozens of species recorded there till now. All species presented in this study were caught using the IBL-5 barrier traps located in four forest districts in the Kampinos Forest. Tingis crispata (the first locality in Masovian Lowland), Aradus brevicollis, Eremocoris plebejus (the second locality in the Masovian Lowland), Cyphostethus tristriatus, Ischnodemus sabuleti, and Monalocoris filicis (the third locality in Masovian Lowland) were among the colected species. IBL-5 traps are used in many studies of saproxylic fauna in Poland, but results of research on Heteroptera with use of these traps have never been published before.