The archaeological contexts of Neolithic obsidian stone tools excavated on the Korean Peninsula were examined, and their regional characteristics were identified in this paper. Based on the most recent results of source identification analysis undertaken on obsidian unearthed from the Korean Peninsula, it was possible to explore certain issues relating to long-distance exchange between regions and social movements in the Neolithic Age. There are a few obsidian sources in the northeast region of the Korean Peninsula, where obsidian was used to make stone tools from the early Neolithic. The systematic operation of the Mt. Baekdusan obsidian supply chain in the late Neolithic resulted in the active use of this obsidian. Obsidian continued to be used even into the early Iron Age. In the southern region of the peninsula, numerous types of obsidian from Kyushu in Japan (Koshidake, Yodohime) were actively used for stone tool production in the early and late Neolithic. This obsidian had been transported across the Korea Strait by the Neolithic people of the Korean Peninsula and the Jomon people of Kyushu on log boats and was mainly used for small sized stone tools such as arrowheads, scrapers and knives. In the Mid-western regions of the Korean Peninsula, obsidian stone tools were used only in the late Neolithic. These obsidian stone tools appear to be related to those of the northeast region. In the Early Neolithic, obsidian from Mt. Baekdusan found its way to the southern region through the Mid-eastern regions of the peninsula. In the late Neolithic, it spread to the Mid-western regions as well. The movement of obsidian found at the site of Cheoyong-ri in Ulsan appears to have been closely related to the exchange network that was formed along Korea’s eastern coast. The presence of obsidian from Mt. Baekdusan in the Mid-western regions of the Korean peninsula is an important fact that illustrates the nature of exchange which took place, through obsidian, between these regions and the northeast region and Russian Primorsky Krai. In particular, it suggests the possible presence of obsidian arrowheads in the Mid-western regions of the Korean Peninsula, which may be discovered in the future. By examining the exchange of obsidian (analyzed as originating from Kyushu in Japan), along with the exchange of stone tools and pottery, the direction and characteristics of trade between the Korean Peninsula and the Japanese Archipelago in the Neolithic Age was explored.