During a revision of the Thuidiaceae for Brazil, we found a new species of Thuidium endemic to Brazil. It occurs in the south, southeast and midwest regions of the country, in the Atlantic Forest and Cerrado regions, and is considered near threatened. Thuidium bifidum is mainly characterized by bifid papillae and short-celled paraphyllia. Details of its morphological characters are illustrated and the geographical distribution mapped. A key to the species of Thuidium in Brazil is also provided. © 2015 by The American Bryological and Lichenological Society, Inc.