The current stage of biosphere development is characterized by rapid urban growth.What rodent species live side by side with people? How does their diversity vary in space and time? Using GIS technology,we have studied the rodent species composition in urban ecosystems of different Russia regions.We have created maps for two groups of rodents.The first group (Mus musculus (s.l.) ,Rattus norvegicus and R.rattus) inhabit buildings and central parts of cities.These urban rodents form communities which are similar in many regional cities.Their invasions are continuing in NE Russia.The second group (about 40% of the rodent fauna of Russia) inhabit urban areas outside buildings.The peak of urban species diversity observed in the European part of Russia occurs at the junction of steppe and forest zones.Rodent communities in urban areas have some regional features which differ from communities in the surrounding natural ecosystems in the Central and Far East Russia (densely populated areas) ,but are similar to natural rodent communities in less developed regions.Changes in rodent species composition in peri-urban areas are being observed.For example,Apodemus agrarius and Microtus levis appeared in eastern Russia,while Castor fiber has become more common in western Russia.