Included on the Brazilian Official List of Species Threatened with Extinction (Lista Oficial de Espécies Brasileiras Ameaçadas de Extinção, Edict No. 1.522/19th December 1989, see Bernardes et al. 1990; Fonseca et al. 1994), and likewise on the regional threatened species list of the state of São Paulo (Brazil, São Paulo SMA, 1998). It is listed on Appendix I of CITES.

The species is recorded from Morro do Diabo State Park (34,441 ha, of which 23,800 ha is forest), and Caetetus State Ecological Station (2,178 ha). A new (federal) Ecological Station of 5,500 ha was decreed in July 2002 – Mico-Leão-Preto Ecological Station in São Paulo. It covers three forest fragments containing Black Lion Tamarins.

The isolation and small size of the existing populations is being addressed through metapopulation management, which includes the captive population founded on individuals taken from the Morro do Diabo State Park, in the 1970s and later, in 1983-1985 as part of the rescue operation in the inundation area of the Rosana hydroelectric dam (Rylands et al. 2002a). Current efforts are focussing on the genetic health of these populations (translocation, managed dispersal and re-introduction) (Valladares-Padua et al. 2000; Valladares-Padua, Ballou et al. 2002), environmental education (Pádua and Valladares-Padua 1997; Pádua et al. 2002), the preservation of remaining forest fragments, with and without lion tamarins, and the creation of corridors to link forest patches to establish larger areas of continuous forest (Pádua and Valladares-Padua 1997; Cullen Jr. et al. 2001; Valladares-Padua et al. 2000; Valladares-Padua, Ballou et al. 2002; Valladares-Padua, Padua et al. 2002).

There is a well-managed captive breeding programme, although it has not been as successful as those for Leontopithecus rosalia and L. chrysomelas, probably because of a very reduced founder stock (Ballou et al. 2002). However, it is growing and, despite having few founders, is now also contributing significantly to the metapopulation management programme currently udnerway by Valladares-Padua and his team (Valladares-Padua and Ballou 1996; Valladares-Padua and Martins 1996; Valladares-Padua 1997; Valladares-Padua et al. 2000; Medici 2001; Valladares-Padua, Ballou et al. 2002). The first translocation of a wild L. chrysopygus group was carried out in 1995, and the first experimental re-introduction, was carried out in July 1999 by combining an adult male born in the Jersey Zoo, UK, with two wild females (Valladares-Padua et al. 2000).