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Japan may have >20% of the world's population of Asiatic black bears (Ursus thibetanus), but local extinctions may result in decreasing populations of the Japanese subspecies (U. t. japonicus). Apparent decreases seem to be related to loss and fragmentation of habitat, a liberal permit system for depredation kills, and a lack of ecological data to develop management guidelines. From 1996 to 1999, we studied bear habitat relationships at 2 spatial scales in the central mountain region of Japan. We used classification and regression tree analysis (CART) to determine the hierarchical structure of bear use of available habitats. The landscape analysis focused on Nagano Prefecture (approximately 13,585 km2), of which bears occupy 60%. Land-cover and land-use data were summarized and compared with the percent of occupied bear habitat within each of the 120 municipalities within the prefecture. The greatest distribution of bears occurred in municipalities with relatively little (<16%) agricultural land use. In areas with >16% agriculture, the presence of national park land and limited human development (<9%) characterized areas occupied by bears. At the local scale within Nagano Prefecture, we determined habitat preference with locations of 13 radiocollared bears. Bears used oak (Quercus spp.)-dominated deciduous and planted, mixed forests in the montane zone (<1,460 m) more than expected. Habitat use at the local scale appeared related to the distribution of natural food resources, particularly hard mast, whereas our landscape analysis indicated that municipalities with abundant bear habitat were primarily associated with areas where agriculture was limited. Because of the complex topography in Nagano Prefecture, agricultural and developed areas often are directly adjacent to bear habitat. Recent patterns of human development have been more diffuse, which may negatively affect resource use on a local scale and bear distribution on a landscape scale.