Food habits of sika deer Cervus nippon show great variations at a macro-scale geographical range and some variations even at micro-scale of locations such as islands or mountains, but there is no study at meso-scale. We investigated variation in the food habits of sika deer over a meso-scale range encompassing high mountains and hilly areas in Tochigi Prefecture, central Japan. Rumen contents sampled from deer culled in the winter of 1996 (n = 147) in 10 localities were analyzed using the point-frame method. Local variation in food composition was high. Detrended correspondence analysis (DCA) showed that food composition varied from the western high mountain region, where low quality foods (dead leaves, bark, and culms) were dominant, to northern and eastern areas, where a dwarf bamboo Sasa nipponica, which grew in the understory of oak forests, was dominant. Two intermediate localities between the western and eastern areas and another eastern locality fell between the western high area and the eastern low area in the ordination. The proportion of S. nipponica varied from 0% to 99% among all samples, and from 0.5% to 60% among the 10 localities. S. nipponica occupied >50% of rumen contents in 52 samples (35.4%). Thus, the food habits of sika deer varied greatly, even within a meso-scale range of 2000 km², depending on food availability in the different habitats.