Abstract: The room-pillar mining method is suitable to horizontal or nearly horizontal ore body.On the premise of keeping safety of the stope，it is important to select reasonable parameters for improving high recovery and lowering ore dilution ratio and loss rate.The finite-difference software FLAC_3D  was adopted to build mechanical model of stope structure for horizontal ore，and the numerical simulation was conducted.Then，the influence of structural parameters to the stope stability was analyzed.Aiming at gentle inclined thin ore body in Western Hubei，and by the numerical simulation，the optimum structural parameters were obtained，and ore recovery rate was obtained accordingly，and then the functional relationship of recovery with depth varied was gained.

Key words: Room-and-pillar mining method, Stope stability, Numerical simulation, Parameter optimization