The Tigers announced the move Wednesday, saying Bosio's contract was terminated because of insensitive comments that violated team policy.
The team says it holds employees "to the highest standards of personal conduct on and off the field," adding it has zero tolerance for Bosio's behavior.
The Tigers say they will not have further comment on the matter.
Bosio was in his first season as Detroit's pitching coach after serving in the same role for six years with the Chicago Cubs.