This paper reports the occurrence of ticks on different species of free-ranging wild mammals in Emas National Park, Goiás State, Brazil. Between November 1999 and July 2008, ticks were collected from free-ranging wild mammals during 330 capture events. The tick species Amblyomma cajennense (Fabricius, 1787), Amblyomma coelebs Neumann, 1899, Amblyomma naponense (Packard, 1869), Amblyomma ovale Koch, 1844, Amblyomma parvum Aragão, 1908, Amblyomma tigrinum Koch, 1844, Amblyomma triste Koch, 1844, and Rhipicephalus microplus (Canestrini, 1888) were identified on hosts of the order Carnivora. Among other host orders (Xenarthra, Artiodactyla, Perissodactyla, Rodentia, Didelphimorphia, Primates), specimens of A. cajennense, A. coelebs, A. ovale, A. triste, Amblyomma pseudoconcolor Aragão, 1908, A. naponense and Amblyomma nodosum Neumann, 1899 were identified. Although most of the tick-host associations found in this study have been previously reported, this is the first report of adults of A. tigrinum parasitizing a pampas cat, Leopardus colocolo (Molina, 1782), nymphs of Amblyomma parvum and Amblyomma ovale on Cerdocyon thous (Linnaeus, 1766), nymphs of Amblyomma naponense on C. thous and Tayassu tajacu (Linnaeus, 1758), nymphs of Amblyomma triste on C. thous and L. colocolo, nymphs of Amblyomma coelebs on Puma yagouaroundi (Geoffroy, 1803) and Dasyprocta azarae Lichtenstein, 1823, and nymphs of Amblyomma cajennense on L. colocolo, Conepatus semistriatus (Boddaert, 1785), Galictis cuja (Molina, 1782) and Nasua nasua (Linnaeus, 1766). This study is therefore a significant contribution to our knowledge of the ectoparasites associated with free-ranging Brazilian wild mammals.