The bumble bees of Taiwan are taxonomically reviewed and keyed. Eight social species and one social-parasitic species are recorded. Distribution ranges within Taiwan are plotted, based on examination of about 4500 specimens. Taiwan ranges of the honey bee Apis cerana, and the stingless bee Trigona ventralis are estimated, with discussion of possible competitive displacement by honey bees of other social bees. Some notes are given on the incidence of uropodid mites on queens, workers and males of Bombus wilemani. A key to the large carpenter bees (Anthophoridae: Xylocopa) of Taiwan is appended.