Abstract: For the complexity of mining conditions in metal mine continuous tailings backfilling mining method，elastic-plastic finite element analysis method was adopted.The plane strain mathematical model was founded for stope roof stability analysis and structure parameters optimization design.The results showed that the fundamental measures to maintain the basic stability of stope roof was controling the stope span or exposed area.For single ore body minning，with the increase of stope span，roof pre-stress stress increased accordingly，and when mining height increased，the maximum principal stress and the maximal shear stress and subsidence of roof were growing larger around the stope，but the tensile stress in the roof decreased gradually.For 1# ore body，recommend stope roof area was about 600 m² limit exposure.Based on this to make stope longer and wide，stope roof stability was the best.

Key words: Filling, Stope roof, Stability, Finite unit, Numerical analysis