The work aims to analyze the cause of blocking according to the working condition of material blocking in the daily work of screw feeders, seek new structural improvement methods to alleviate the formation of material blockage and improve the working performance of screw feeders. Firstly, the fixed pitch screw structure was designed through the conventional fixed pitch design method, and then the equiangular conical screw was used to design the variable diameter and variable pitch structure in the feeding area. The two design results were modeled by SolidWorks, and the fixed pitch screw model and variable diameter and variable pitch screw model were respectively imported into the discrete element simulation software EDEM for performance simulation analysis. The analysis results showed that compared with the fixed pitch feeding screw, the feed flow in the feeding area was uniform and there was no formation of material inclined plane. In the same time period, the material conveying rate was significantly increased by 8.7% and the material mass flow rate was significantly increased by 12.2%. The design of variable diameter and variable pitch in the feeding area effectively improves the stability of the material flow, makes the material flow in front and behind the feeding area uniform, solves the machine blocking problem of the screw feeder from the source, and improves the transmission efficiency of the screw conveyor under the same design requirements, which has reference significance for solving the machine blocking problem of the screw feeder and the structural design of the variable diameter and variable pitch screw.