Abstract: Abstract: According to the problem that the surface subsidence cannot be controlled in a mine in Jining by the full mining and backfilling mode of solid backfill mining. The necessity of solid backfilling strip mining is analyzed, The yield zone width of coal pillar under the action of backfill is deduced. The design method of width considering the stability of coal column is presented. The mathematical expressions of recovery rate and surface deformation are derived. The variation law of the stress concentration coefficient of coal pillar is studied, which provides support for the parameter selection of the mechanical model by adopting the research method. Combining the results of theoretical analysis and numerical simulation, the width of mining and coal pillar of solid backfilling strip mining are optimized. Results showed that when the mining width is 53 m and the width of the coal pillar is 25 m, surface deformation is controled, ensuring stability of coal pillar and improving resource recovery rate.