Affected by the adjustment of Wujaingdu hub on the upper reaches, the stage between Wujiangdu hub and Xuantang changes abruptly. Establishing two-dimensional unsteady flow model of waterway on the lower reaches of Wujiangdu hub, we verify the prototype level and flow distribution, calculate the propagation process of unsteady flow wave under different working conditions, and study the impact of propagation of Wujiangdu hub unsteady flow on waterway of the lower reaches.