The new species Brickellia jimenezii Hinojosa & Cruz Durán (Asteraceae, Eupatorieae) is described from Guerrero, Mexico. It belongs to the Barroetea A. Gray complex within Brickellia Elliot, and is similar to B. subuligera (Schauer) B. L. Turner. The new species presents heads with more florets ([45 to]74 to 106 vs. 30 to 50 in B. subuligera), larger style branches and anthers (to 3.7 mm and 2.1 mm, respectively, vs. to 2 mm and to 1.3 mm, respectively, in B. subuligera), as well as cypselae with four well-defined ribs on each face (vs. none or two on the exterior face and none or one on the interior face in B. subuligera). A key to this species complex and an illustration of the new species are provided.