Abstract: Regional provenance analyses of obsidian have enabled to identify so far twelve sources in Northwest of Argentinaand defined two main and stable areas of distribution along the pre-Hispanic period. The aim of this paper is to report the first analyses carried out on obsidian artifacts recovered from two archaeological sites of the Tafí valley (Tucumán, Argentina), dating to the first and second millenniumCE.The study addresses the sourcing and use of this raw material in their contexts, as well as the inclusion of the study area within the obsidian distribution circuits in the Northwest of Argentina. The methodology included techno-morphological and morphological-functional analyses as well as chemical provenance studiesusing x-ray fluorescence (ED-XRF).The results enabled usto detect, so far, the use of the Ona-Las Cuevas source, located approximately 240 km far from Tafí valleyin the southern puna of Argentina(Catamarca province);and to suggest the implementation of indirect procurement practices within complex distribution circuits. We have also established that the obsidian artifacts would have been used intensively in daily activities which were part of household organization, such as long-distance relationships, hunting and processing food. Based on this information, we discuss the practical uses of obsidian, as well as other possible roles of this raw material in pre-Hispanic contexts which contribute to broaden knowledge about the cultural developments of Tafí valley. Keywords: obsidian; Tafí Valley; circulation; daily practices; pre-Hispanic contexts