We present a description of macro- and microscopic taxonomical features of a medicinal mushroom, Ganoderma oerstedii, based on Mexican specimens from the states of Chiapas, Morelos, Sinaloa, and Veracruz, and discuss its relationships with species of the G. lucidum complex. A phylogenetic study based in rDNA sequences of a specimen of G. oerstedii from Veracruz is presented, as well as a review of traditional and modern uses in medicine.