The Black-faced Lion Tamarin occupies the southernmost limits of the distribution of the callitrichids. The type locality is on the north-eastern part the island of Superagüi, on the coast of the state of Paraná. Other groups have been found elsewhere on the island, except in the extreme north and some higher elevations in the south-west (Persson and Lorini 1991, 1993). These authors found L. caissara on the mainland, in parts of the valleys of the Rio Sebuí and the Rio dos Patos, limited in the north by the Rio Varadorzinho, and to the west by the Serra da Utinga, Morro do Bico Torto, Morro do Poruquara, and Serra do Gigante. Persson and Lorini (1991, 1993; Lorini and Persson 1994a,b) estimated that its entire range is less than 300 km². Four groups have been found to the north, also on the coast, in the municipality of Cananéia in the state of São Paulo (Persson and Lorini 1993). Martuscelli and Rodrigues (1992) reported four localities in the extreme south-east of São Paulo, two in the basin of the Rio do Turvo (Rio do Turvo and Morro do Teixeira, localities 1 and 3, map p.922), and two further north in the region of Itapitangui (localities 13 and 14, map, p.922), opposite the Ilha Cananéia. As a result of interviews of local people, Martuscelli and Rodrigues (1992) also indicated that L. caissara may occur further inland, at two localities: the Rio Taquari (locality 11, map p.922) and the Rio Ipiranguinha (locality 12, map p.922). The latter may refer to Jacupiranga State Park (100,000 ha, although a large part of it is no longer forested), but none of these localities have been confirmed. Field surveys by Valladares-Padua et al. (2000) in the municipalities of Jacupiranga and Pariqueraçu failed to obtain any evidence of the existence of L. caissara. However, they were able to confirm its presence between the villages of Ariri and Taquari, in the municipality of Cananéia, as had been reported by Martuscelli and Rodrigues (1992), and Valladares Padua et al. (2000) have suggested that its range may extend only a short distance north.

The distirbution of L. caissara is reviewed by Rylands et al. (2002b).