Forty-one fragments of obsidian implements collected from three layers of Danma site, one layer of Miyaato site, and one layer of Himemiya site of the Jomon age in the Izu peninsula were analyzed for 8 major elements by the energy-dispersive x-ray microanalyzer, and the results were compared with those of more than 100 raw samples from 29 main outcrops in central Japan. These samples were also examined for their crystallite types. Both results showed the identity of provenance strictly in 46%, and roughly in 78%. Most of the implements were made from the raw obsidian derived from Izu-Shichito area, and small amounts from Kashiwa-toge in Izu peninsula. -- AATA