Abstract: To address the problems of poor material loosening, severe screen aperture blockage, and low undersize passing efficiency encountered in the 3 mm dry screening of sticky-wet thermal coal, a coupled bidirectional simulation method integrating the Discrete Element Method and Multibody Flexible Body Dynamics was employed. A screening test system equipped with a 3 mm elastic screen deck was developed, with sticky-wet coal (external moisture content of 12.58% and a dominant particle size range of 3~0 mm) used as the research material. Kinematic simulations of the screen deck under unloaded conditions, dynamic behavior analysis of the material bed, and kinematic response analysis of the elastic screen deck under material impact were conducted. Meanwhile, screening performance optimization tests were carried out by adjusting the excitation force, excitation frequency, and feed rate. The total misplaced material content, screening efficiency, oversize misplacement rate, and undersize misplacement rate were adopted as evaluation indices.The results show that under unloaded conditions, the mean displacement and maximum acceleration of the elastic screen deck were 4.37 mm and 54.09 m/s², respectively, representing increases of 36.14% and 66.89% compared with those of the screen body. The impact of the material bed substantially increased the deformation of the screen deck, effectively alleviating screen aperture blockage. The maximum deformation under loaded conditions reached 6.89 mm, which was 4.56 times that under unloaded conditions, while the peak stress of the screen deck at the instant of material impact reached 0.725 N/mm². Screening efficiency first increased and then decreased with increases in excitation force, frequency, and feed rate. The optimum screening performance was achieved at an excitation force of 7.0 kN, a frequency of 16.0 Hz, and a feed rate of 2.0 kg/s, with a screening efficiency of 89.01%, a total misplaced material content of 5.52%, an oversize misplacement rate of 12.51%, and an undersize misplacement rate of 2.31%. Clarifying the interaction mechanism between the elastic screen deck and the material bed provides quantitative guidance for optimizing the structure of elastic screen decks, extending their service life, and reducing equipment wear. The optimum process parameters obtained in this study provide theoretical support and a technical basis for the design and field operational control of dry screening equipment for sticky-wet fine-grained coal.