We assessed the distribution and status of jaguar Panthera onca in the Argentine Chaco, one of the least known areas within its range. Current jaguar distribution in the Chaco encompasses parts of central and western Formosa, western Chaco, eastern Salta and north-eastern Santiago del Estero Provinces. Jaguar range was reduced following colonization of the semiarid Chaco even though there has been little deforestation. Jaguars have not been observed over the last 15 years in areas where colonization occurred more than 35 years ago, probably reflecting hunting pressure. Livestock predation is lower now than when the area was first settled in the 1920s. This may indicate low jaguar densities as the livestock management system has not changed. Local people, however, continue to hunt jaguars with the intention of exterminating them. Education, enforcing jaguar hunting laws, increasing control of poaching in protected areas, and creating more protected areas may be the most efficient strategies to preserve the jaguar population of the Argentine Chaco.