Abstract: In the 1980s, the academic circle stated a heated debate about the key issue in the construction history of Dujiangyan.It was finally settled with recognition of "Kaiming's excavated river from Yulei Hill".But, in the past twenty years, a large number of unearthed ancient cultural relics throw doubt upon this statement, and set reconsideration on it.This paper studies on the excavation date of Baopingkou and other related questions.