North Yuan was the continuance of foe Yuan Dynasty. Moot part of Jinn belonged to the sphere influenced during the reign of Nahachu of the North Yuan, and Fuyu was its centre area. Although the Yuan Dynasty lasted more than one hundred years, there were few relics confirmed to be of the Yuan Dynasty by recent archaeology surveys. On the background of historical course of foe North Yuan and the Yuan Dynasties in Jinn, based on the observation, comparisons and researches on the relics and ancient traces unearthed from ibis region, the author corrected the deviations which existed in the archaeological division of history between the Yuan and Ming Dynasties.