For understanding the mechanisms of biological coexistence, investigations of resource use by predators are highly important. Although time, habitat, and diet are considered the three major resources in niche partitioning, studies that have comprehensively investigated these three resources in predator guilds have been limited. Snakes are suited for studies on the role of interspecific competition and niche partitioning, and dietary resource has been considered as a fundamental variable that allows snakes to coexist. However, terrestrial snake communities in temperate regions are very variable in terms of their coexistence dynamics and have shown no evidence of generalized patterns. Here, to clarify the coexistence mechanisms of terrestrial snakes in temperate regions, we assessed which niche type is predominantly used for their coexistence on a Japanese island rich in snake species. Specifically, we investigated daily and seasonal occurrence as temporal niches, landscape-level distribution as a spatial niche, and stomach content as a dietary niche. We found that niche partitioning in all three major resources occurs among the all seven snake species on the island. Daily occurrence was partitioned into three groups; completely diurnal and nocturnal, and active during both time periods. Seasonal occurrence was partitioned into three groups; widely active from spring to autumn, mainly active in summer, and mainly active in autumn. Distribution was partitioned into two groups; high distribution probability even in mountain areas and mainly in lowlands. Food habit was partitioned into three groups; mainly feed on rodents, mainly feed on frogs, and mainly feed on earthworms. Taken together, although our study did not answer the question of which niche type is predominantly used for terrestrial snake coexistence in the temperate region, our results suggested that the snakes of the island may have been able to coexist by increasing the dimensions of the niche to be partitioned due to intense competition in one niche according to the hypothesis of niche complementarity. Moreover, we provided empirical evidence that snakes can coexist through multidimensional niche partitioning, i.e., spatiotemporal resources are also important force in terrestrial snake coexistence.