This study aimed to provide a list of fish species from tributaries of rio das Almas and rio Maranhão basins, in the upper rio Tocantins basin, Goiás State, Brazil. For this study 21 stream stretches were sampled during the dry season in July 2010. A total of 2,279 individuals of 67 species, 19 families and five orders were collected. The most representative families in number of species were Characidae, Loricariidae, and Crenuchidae respectively. The genus Knodus, Hypostomus and Characidium showed the greatest abundance and distribution among the samplings. Poecilia reticulata was considered the only non-native species. The presence of a large number of endemic and undescribed species or with undefined taxonomic situation, in addition to the rapid habitat loss in this region, juts the need for the development of further studies in this basin.