Abstract: In response to the phenomenon of varying degrees of spalling of coal walls under the conditions of large mining height in soft coal seams,taking the large mining height working face of a soft coal seam as the research background,a research method combining numerical simulation and on-site measurement was used to study the prevention and control of coal wall spalling in the large mining height working face of soft coal seams. Firstly,COMSOL Multiphysics was used to simulate and analyze the grouting diffusion law under different parameters,the grouting scheme is determined as 15° dip angle of grouting hole and 7 MPa of grouting pressure. Marked maximum effective diffusion range of grout simulation results was imported into Auto CAD and then into FLAC^2Dto study the plasticity zone of local grouting. The results show that the plasticity zone in front of the working face decreases obviously before and after grouting. The grouting simulation results of deep and shallow holes through faults and special structural periods show that the grout can fully permeate the whole coal body of working face and improve the coal wall consolidation. On-site monitoring shows that before and after grouting,the number of coal wall spalling is reduced by 70%.