[in German with English summary: ] The City Nature Challenge (CNC) from iNaturalist is a competitive event between cities and carried out since 2016 - initially only in the USA - with the aim of collecting as much data as possible about the occurrence of species using georeferenced, digital photos or recordings. The gained data should create a better basis for biodiversity studies and also promote environmental awareness. This article analyzes the results of the documented observations made between April 30 and May 3, 2021 in Austria and in particular for Graz and the Graz-Umgebung district. A total of 33,585 observations and at least 3,498 different species were uploaded across Austria. Graz achieved first place within Europe with 17,189 observations. In terms of documented species, Graz even achieved 10th place worldwide out of 419 participating areas. Interesting results are a newly recorded lichen species for Austria, Flavoparmelia soredians as well as the faunistic peculiarities Bucculatrix argentisignella and Chrysoesthia cf. verrucosa, new records for Styria among moths. Two beetles, the carrion beetle Ablattaria laevigata and the weevil Calosirus terminatus, were rediscovered for Styria. Key words: iNaturalist, City Nature Challenge, Biodiversity, Styria, Austria.