Abstract: A certain iron mine adopts the stage open stope and subsequent filling method. At present， the stoping work of the first mining middle section of -450 m is about to end. It is planned to increase the stage height from the original 60 m to 90 m in the development of the new middle section of -390 m， and the stage height is increased by 50%. In order to study the stress and deformation law of steeply inclined thick ore body under the condition of stage open stope and subsequent filling mining， this paper adopts the method of combining similar material test and numerical simulation， considers the influence of the first mining middle section and multi panel area on the new middle section mining and filling， and obtains the stress and deformation law of stope pillar and surrounding rock through analysis.The results show that: in the process of mining and filling in the new middle section after the stage height is raised， the stress in the pillar will increase greatly after the pillar is exposed， and the shear failure of the pillar will be caused with the increase of stress concentration； The maximum deformation in the stope appears in the roof of the room in the middle panel， the maximum principal stress and plastic zone appear in the middle and lower position of the middle pillar， the maximum principal stress， settlement deformation and plastic zone are symmetrically distributed with large in the middle and small on both sides， and the minimum principal stress appears at the top corner of the room on both sides； The minimum principal stress and settlement deformation caused by interval mining are less than those caused by sequential mining， while the mining sequence of chamber has little effect on the maximum principal stress； With the increase of pillar width， the maximum and minimum principal stress， deformation value and plastic zone range in stope decrease gradually. The research results of this paper can be used for reference for similar mines at home and abroad.

Key words: deeep mining, similar materials, backfill mining, subsequent filling, numerical simulation, stope stability