Parasites collected from free-ranging black bears, Ursus americanus Pallas, 1780, from northeastern Minnesota or northern Michigan include the dog tick, Dermacentor variabilis (Say, 1821), the winter tick, D. ALBIPICTUS (Packard, 1869), a louse, Trichodectes pinguis euarctidoes Hopkins, 1954, an ascarid worm, Baylisascaris transfuga (rudolphi, 1819), a filarial worm, Dirofilaria ursi Yamaguti, 1941, taeniid tapeworms, and unidentified fleas. The broad fish tapeworm, Diphyllobothrium latum (linnaeus, 1785), was reported to be common in man and black bears in northeastern Minnesota earlier in this century, but now it apparently is uncommon in black bears in norther Wisconsin. Cannibalism of carcasses is common in the black bear and may play a major role in the transmission of Trichinella.