The invention provides a flow process rasterization method based on soil infiltration capacity. The flow process rasterization method comprises the steps that S1, a flow process line of a drainage basin outlet section is converted into a water level process line through a water level-flow relation curve; S2, flow distribution weights in different grids is determined according to the land utilization type and the soil characteristic data; S3, the distribution proportion of runoff of different grids is determined, and the distribution proportion of all grids in the drainage basin is calculated according to the flow distribution weight of each grid; and S4, the flow of the basin outlet section is distributed into each grid according to the distribution proportion to achieve flow rasterization. According to the method, the influence of soil infiltration capacity of different grids of the drainage basin on the runoff yield is considered, the drainage basin runoff yield and confluence mechanism and the physical mechanism of the hydrological process are followed, the calculation error problem caused by average distribution is reduced, and the calculation process is simple, easy to operateand easy to popularize.