The Taoyuan hydro-junction ship lock is located at the tail of the central bar. In the middle water period，the plunging flow is from both sides of the hydro-junction，which causes the problems of transverse current and sand deposition in the downstream approach channel and its entrance area of the ship lock. It is necessary to solve the problem through engineering measures. The fixed bed flow and fixed-bed sediment transport experiments are carried out to study the flow and sediment conditions in the navigation hindering reach under the different regulation work plans of the middle water period. The results show that：1） The left dredged area can effectively balance the lateral drainage effect caused by the right dredged area. The wider is the width of the left dredged，the smaller are the transverse current velocity and the volume of the sand deposition in the reach. Comparing to the vertical wall construction，the ramp-style gabion dam can effectively avoid the reverse current formed at the end of the dam，so it further reduces the transverse current velocity and the volume of the sand deposition in the reach in the middle water period. 2） A dredging area is arranged along the entrance area of the downstream approach channel and the left side of the connecting section. The dredging width is equal to 1.5 times the width of the approach channel，and the dredging bottom elevation is 26.44 m. At the same time，the slope-type gabion dam is used to extend the left guide wall by 200 m，which can better solve the navigation-obstructing problem in the middle water period.