A faunal butterfly study was conducted in a semi-deciduous tropical forest of Tzucacab, to the south of the state of Yucatán. During the rainy season, from May to October 2012, butterflies were collected at 18 sites. A total of 1,035 individuals belonging to 6 families, 82 genera and 99 species were obtained, of which 4 species are new records for the State of Yucatán. The family Nymphalidae was the most diverse with 42 species, followed by Hesperiidae (19), Lycaenidae (14) and Pieridae (13). The less diverse families were Riodinidae (7) and Papilionidae (5). The butterflies were mainly nectarivorous (41.4%), in less percentage yeast-feeding (19.2%) and mud-puddling (1%); 38.3% had more than one feed habit. Species richness of butterflies found in this area corresponds to 28.5% of the species recorded for Yucatán.