Abstract: Aiming at the problems of low production capacity and high labor intensity caused by over-conservative stope span of up and down filling mining method in Linglong gold mine, FLAC^3D software was used to simulate and optimize stope structure parameters.The simulation results show that the limit span of the stope is 8m under the current field geological and technical conditions.In view of the simplicity of the simulation and the complexity of the field conditions, it is recommended that the stope span should not exceed 6m during production.Compared with the technical and economic indicators before and after the stope span changes based on industrial tests.The test results show that the loss rate and dilution rate are significantly reduced after the span is expanded to 6m, and the production efficiency is improved.After the span is expanded, large drilling and drilling equipment is introduced to improve the degree of mechanization and reduce the labor intensity of workers.