Winthemiini is a worldwide tribe in the subfamily Exoristinae (Diptera: Tachinidae) with 200 species in 16 genera. We confirm the monophyly of Winthemiini and examine relationships among the constituent genera based on a parsimonious analysis of adult morphological characters for 53 species representing 12 out of 16 currently recognized Winthemiini genera. As a result, Winthemiini is divided into three major clades, with relationships as follows: ((Rhaphiochaeta [Ossidingia, Nemorilla]) ((Hemisturmia [Avibrissosturmia, Triodontopyga]) ([Smidtia, Winthemia])). A revised classification system for Winthemiini is proposed, recognizing 12 genera. Four new synonymies are proposed – Diotrephes and Chesippus as junior synonyms of Smidtia, and Hemisturmiella and Parachetolyga as junior synonyms of Winthemia – along with four new combinations: Winthemia brasiliana (Guimarães) comb.n., W. metopia (Bischof) comb.n., Smidtia atriventris (Walker) comb.n., and S. notialis (Reinhard) comb.n.