Abstract: Objective In order to strengthen the screening performance of the traditional vibrating screen, this study takes iron tailings as the research object, and constructs a new type of composite vibrating screen according to the synthetic vibration theory of Lissajous. Method EDEM software was used to establish three particle size classes of particles as screening materials, and discrete element comparison simulation studies of linear vibrating screen and composite vibrating screen were carried out at the same vibration parameters. Result The study shows that due to the composite vibration in xyz three directions there are sub-vibration, so that the mineral particle group force is more diversified, the degree of looseness is large, the stratification effect is good, and the mineral particles are more evenly distributed on the screen surface. Compared with the linear vibrating screen, the composite vibrating screen has greater advantages in screening processing capacity, screening efficiency and other aspects. Conclusion Quantitative calculations have found that the composite vibrating screen obtains a screening efficiency of 94.95% at smaller vibration parameters, which is 3.25% higher than that of the linear vibrating screen.