Abstract: There are some adverse changes in the river regime in the south channel of the Yangtze River estuary in recent years, where the deep channel widening appears in the lower section of the south channel， especially the development of central string, ditch and the scouring along the middle and lower sand body. It has brought remarkable influences upon the deep waterway′s maintenance and the stability of surrounding waters. In order to solve those problems， the Ruifengsha regulation works are proposed. In this paper， the efficience of Ruifengsha regulation works and their influences on the surrounding riverbed evolution are analized by using physical model tests and numerical model tests, and by considering riverbed evolution. The analysis results show that Ruifengsha regulation scheme RFS10 can protect Ruifengsha from scouring， improve navigation conditions in the south channel， reduce bottom sand flowing into the north passage， improve maintenance conditions of the south wharf frontier in the south channel， and stabilize water depth in Changxing waterways. It has almost no effects on the maintenance conditions of Yuanyuansha waterway. And it has no potential adverse impacts on the surrounding river regime.