Based on the one-dimensional and two-dimensional unsteady-fractal mathematical model of Yibin to Zhutuo reach downstream Xiangjiaba dam,we research the flow conditions and local beaches with the cumulative and variable dimension fractal method and obtain the channel length of river profile fractal dimension and fractal dimension river cross-section width.We also probe into the response of the river profile fractal dimension and river channel transverse section to the fractal dimension of navigation hydraulic indices.The results show that:1) in Yibin -Zhutuo river reach,with the decrease of the longitudinal profile fractal dimension,the river cross-section fractal dimension turns smaller gradually;2) under the condition of meeting the requirements of the lowest navigable flow,the profile fractal dimension values of Yibin - Luzhou section is within the range of -1.297～-1.049,and that of Luzhou-Zhutuo section is within the range of-1.305～-1.032;3) in Yibin-Zhutuo river,under a certain flow cross-section,the fractal dimension numerical reflects the degree of correlation of the terrain and traffic,while beach profile fractal dimension reflects degree of correlation of the whole river topography and discharge process.