To explore the motion characteristics of maize mixture on the bionic screen designed based on the earthworm motion characteristics, the non-harmonic motion of the bionic screen in EDEM was realized by using API, and computational fluid dynamics and discrete element method (CFD-DEM) were coupled to simulate the motion of maize mixture under the combined action of airflow and bionic screen. The mechanism of maize mixture migrated on bionic screen was clarified by analyzing their screening process. The horizontal migration and vertical stratification of maize mixture in different areas of bionic screen were studied. The numerical simulation results showed that the average horizontal velocity of maize grain, cob, and stalk on the bionic screen was 0.63m/s, 1.60m/s and 2.51m/s, respectively, which was conducive to the horizontal separation and dispersion of maize grains and impurities along the screen surface. The average horizontal velocity of the maize mixture in the front of the screen was the fastest, which was 1.71m/s, indicating that the bionic screen could make the maize mixture migrate backward rapidly in the front of the screen to reduce the accumulation at the feeding end. When the maize mixture moved from the middle to the tail of the screen, the average vertical displacement of maize grain was decreased from 40.20mm to 19.59mm, and the average vertical displacements of the cob and stalk were increased from 54.47mm and 71.31mm to 64.31mm and 77.01mm, respectively. From bottom to top, the maize mixture on the screen was maize grain, cob, and stalk, respectively. With the maize mixture migrating backward, the vertical stratification of maize grain and impurity became more apparent. The motion state of the maize mixture on the bionic screen and their horizontal velocity changed were analyzed by the high-speed camera, which was basically consistent with numerical simulation results. The mechanism of maize mixture migrated on bionic screen was verified. When the inlet airflow velocity of cleaning device of the bionic screen was 12.8m/s, and its airflow direction angle was 25°. The maximum concave depth of the screen surface was 50mm, and the rotational speed of the cams were 120r/min.The loss percentage and impurity percentage of maize grain of the bionic screen was 0.61% and 1.94%, respectively, which met the requirements of the national standard. The research result can provide a reference for parameter optimization and the exploration of flexible screening mechanisms of the maize bionic screen based on the earthworm motion characteristics.