Jomon pottery sherds from the shelter site in the Taishaku valley of Japan have been dated by the quartz inclusion technique in which dose-rates were measured by CaSO₄: Tm TL dosimeters. The measurement of environmental dosage was performed by burying a copper tube with the dosimeter in the culture layers of the site. Sherds of all the stages in the Jomon period were dated to elucidate the relationships between the radiocarbon dates and TL dates. The results obtained for sherds from 13 culture layers are in agreement with radiocarbon dates for each stage in the Jomon period. -- AATA