The canton Aargau has a high responsibility for the conservation of riparian areas within Switzerland. In the past years, several conservation measures have been implemented. To assess the effectivity of these measures, a survey of ground beetles was conducted in five different areas. The main goal was to obtain a species list as complete as possible for each of the five areas. In this article, the results of the surveys in the riparian areas Villnachern Schachen, Möriken-Wildegg, Wasserschloss, Rupperswil and Rietheim are presented. In each area, the ground beetles were caught in different microhab itats that were accessible for collection with a battery-operated exhaustor. Examples for such microhabitats are sandy, clayey or muddy areas, populations of reed or reed canarygrass, herbaceous strips and sandy forest-floors. Barely sampled were areas with a thick decaying leaf-cover, hardly accessible thickets of dense populations of blackberry, goldenrod, nettles or jewelweed. A total of 165 species were recorded in this study. Thereof, twelve species were recorded for the first time in the canton Aargau. Another 26 species have only been recorded one to three times up to now. Based on the data of this survey and other data from the canton Aargau, it is estimated that at least 200 species or 80 % of all ground beetle species of the canton of Aargau could be found in riparian areas of the canton. Although the area of the survey covered about 90 ha in total, of which only 22 ha were sampled intensively, we recorded about two third of the ground beetle species ever found in the canton. This underlines the crucial importance of riparian zones and the conservation measures for the ground beetles. Thus, the conservation measures of the canton seem to be very important. Whereever possible, dynamic riparian zones should be created or recently developed ones preserved. Even very small scale restoration measures are promising and increase species richness.