The influence of gaseous air pollutants on moss-dwelling arthropods was studied along an urban-rural gradient. Close to 17,000 individuals were extracted. Oribatid mites and springtails were analyzed to the species level, other microarthropods to the lowest level possible. Community structure (species richness, diversity and abundance) was investigated in relation to air pollution. The results demonstrate that air pollution influences the species composition and population densities of individual taxa. There was a trend of decreasing species richness and more uniform communities (especially for oribatid mites) with increasing pollution. The most promising arthropod taxon as an indicator of air quality is the oribatid mite Zygoribatula exilis (Nicolet). In addition to air pollution, abiotic factors such as relative humidity, substratum and pH seem to have a decisive influence on several arthropod taxa. In comparison to moss-dwelling nematodes and tardigrades, moss-dwelling arthropods are less sensitive to pollution.