Arslantepe is a höyük (i.e. tell), located within the fertile Malatya Plain, some 12 km from the right bank of the Euphrates River. The long sequence of the site covers several millennia, from at least the 6thmillennium B.C. until the final destruction of the Neo-Hittite town. The archaeological site benefits of a more than fifty years of excavations by the Italian Archaeological Mission (La Sapienza University, Rome). Its long history reflects the changing relations and connections with various civilizations in the Near East (Frangipane 2011). During the earliest phases (Chalcolithic), Arslantepe is connected with the Syro-Mesopotamian world. However, during the Early Bronze Age Arslantepe‘s external relations are reoriented towards eastern Anatolia and Transcaucasia. During these periods, Arslantepe also had connections with Central Anatolia that grow during the 2ndmillennium B.C. with the rising Hittite civilization.This talk focuses on the sourcing of obsidian artifacts collected in Arslantepe. Four hundred artifacts, belonging to eight archaeological levels, from Late Chalcolithic to Middle Bronze Age, were analyzed. These analyzes include technological and typological study together with geochemistry using a portable XRF analyzer. The geochemical data have then been compared with the GeObs database which includes more than 600 geological samples, precisely positioned within space (latitude and longitude) and time (according to volcanic and stratigraphic settings). This database includes 14 sources (i.e. volcanoes) and 34 sub-sources (outcrops with specific volcanic settings) from the Anatolian volcanoes. This talk has three main scopes: 1) studying how the procurement of obsidian change according to the technological and typological kinds of artifacts; 2) understanding the changing external relations through time on obsidian procurement, using the very clear archaeological stratigraphy revealed at the Arslantepe; and 3) showing whether the obsidian procurement indicates same spatial and social connections than other artifacts; and presenting when the obsidian procurement show some different patterns.