Biodiversity in urban areas is usually seen as beneficial to the ecosystem and human well-being in the city. Biodiversity in itself, however, includes any kinds of organisms, including pests, which bring about problems when they are found in undesired spaces. Hornets (Hymenoptera: Vespidae) are one of the poisonous pests, which form colonies on the buildings, houses and garden trees in urban areas. In Japan, the problems of some hornet species have been recorded in urban areas since 1970s. Conflicts between urban residents and hornets tend to increase, which can be shown by the annual number of hornets’ nests removed in urban area. In Toshima-ward, 157 nests of 2 species of hornets (Vespa analis, and Vespa simillima xanthoptera) were reported and removed during three years. In 2010, 2012, 2013, 47,66 and 44 nests were reported in Toshima-ward. Nests of hornets were widely distributed. In 2010, 2012 and 2013, nests of hornet were found respectively in 34, 45 and 30 districts. Some districts had more than one nest within a year and some districts had recurrent nests. We seek to understand the relationship between hornets and urban land-use and hope that these results contribute to better management of wildlife in urban areas.