We described a new species of Dendrophryniscus from the Mantiqueira Mountains, a mountain range in the Atlantic Forest in the state of Minas Gerais, Brazil. Dendrophryniscus cuca sp. nov. is known only from its type locality, the private Protected Area Chapadão da Serra Negra, municipality of Santa Bárbara do Monte Verde. The new species is morphologically distinguished from its congeners mainly by the combination of the following characters: medium size for the genus, longitudinal set of granules posterior to the corner of mouth, fingers neither fringed nor webbed, and presence of nuptial pads in males. Molecular analysis of the 16S mitochondrial DNA indicates a genetic distance range from 2.39% (D. brevipollicatus) to 17.92% (D. carvalhoi). Individuals were found in bromeliads, and we described a male–male amplexus with the presence of release vibrations, but calling activity was not observed. This is the fourth endemic anuran species of the Serra Negra da Mantiqueira, part of the Mantiqueira mountain range (Serra Negra da Mantiqueira), highlighting the importance of the region for the Neotropical herpetofauna.