Aiming at the problem of construction sequence arrangement of the channel regulation engineering under the high velocity and deep water in the lower reaches Yangtze River，the research of construction sequence principle and regulation effect of the submerged dyke at the left braided channel of Hechangzhou waterway were carried out by combining mathematical model and river bed evolution analysis.The results showed that the diversion ratio of the left braided channel decreased by 9% after the implementation of the submerged dike,and the navigation channels were deepened obviously due to the riverbed scouring of the right braided channel；the flow fields and topographic adjustment were basically in line with the expectations,and the regulation effect was achieved by that of limiting in the left braided channel and deepening in the right braided channel.The results can provide a reference for the construction sequence research of the navigation channel regulation in the lower Yangtze River.