Abstract: Historical observation data suggests that high velocity systems occurred outside the Yellow River estuary, and on a large time scale, these high velocity systems change with the alteration of the sea channels and the delta itself. This research aims to establish a mathematical model for the Yellow River estuary by using 3 different nautical charts.The tidal prediction software of "China Tide" is adopted to simulate the tide coming offshore. The calculation results show that: ①since 1962, there have been some high velocity systems outside the estuary, for examples the systems located at the Tianshuigou and Shenxiangou; ②in 1976, there were a number of small groups of high velocity systems along the coastline; ③sine 1996, there have been 3 high velocity systems located at the Wanwangou, Shenxiangou and the Qing 8 channel respectively; ④the change of high velocity system is closely related to the evolution of the coast, and the high velocity regions are always located at the place where protrude spits occur.