Three new species of Eriocaulaceae, endemic to the Serra da Canastra in Minas Gerais state, are described. Paepalanthus petraeus is assigned to P. ser. Paepalanthus, differing within the series by its thickened stem accumulating leaf sheaths, linear leaves, and numerous scapes shorter or equaling the leaf height and bearing capitula with brown involucral bracts. Paepalanthus sinuosus belongs to P. subsect. Polyactis and is distinguished by few scapes in lax fascicles, more than twice as long as the leaves, which are patent to slightly recurved, and light brown involucral bracts with acute apex. Syngonanthus culcitosus, within S. sect. Syngonanthus, is unique due to its elongate and branched stem forming dense mats, simple inflorescences, cream-colored involucral bracts equaling the length of the floral disc, and gynoecium with nectariferous appendages. Comparisons with the most similar species are provided for each new taxon. Maps, photographs, and illustrations are presented, together with comments on phenology, distribution, habitat, and morphology. Paepalanthus petraeus and P. sinuosus are likely to be assessed as Critically Endangered, and S. culcitosus as Vulnerable, according to IUCN criteria.