The structure of the iron-bearing charge directly affects the porosity and void ratio of the material layer of the blast furnace burden distribution，and then affects the reasonable distribution of coal gas flow，so it is very important to explore the influence of pellet ratio on the distribution of the material layer and improve the interlayer interface effect. In this study，the discrete element method is used to model the roof area of the 2 550 m3 blast furnace in 3D，and the influence of increasing the pellet ratio on the shape of the charge surface in the presence of coke layer is studied，and an optimization scheme is proposed for the interface effect between the coke layers. The results show that with the increase of pellet mass ratio，the velocity and landing radius of the charge particles at the end of the chute increase，and the fuel flow is more dispersed. With the increase of the chute inclination，the effective length of the chute increases，and the landing radius of the charge increases significantly. Increasing the proportion of pellets in the ferrous charge makes the iron-containing charge roll towards the center of the throat in the radial direction，the overall height decreases in the longitudinal direction，and the seepage phenomenon at the coke interface is serious. Therefore，when increasing the pellet ratio，in order to ensure the stable shape of the initial material surface at the throat，the angle of ore distribution should be increased to slow down the rolling of the iron-containing charge to the center of the throat.