Abstract: In order to ensure efficient production capacity and mining safety of the stope，3D-FEM was conducted to analyze the stability of the stope with different structure parameters and filling ratio based on the analysis of the stope-stability of the key factors and failure mechanisms，and the safe and reasonable stope parameters were selected.Stress，stress distribution area and displacement of stope roof of different structure parameters and fill ratio were calculated and analyzed to judge the stability of the stope at different conditions by adopting the FLAC3D.Result showed that，stability of stope at both sides was obviously affected by the backfill ratio.Stability of the stope was changed less when the backfill ratio varies from 1∶6 to 1∶8.The change rate of the stress and displacement of stope roof was a growing trend，and the stability of the stope was lowered when the backfill ratio was less than 1∶8 and the width of the stope was more than 18metres.So the suggested backfill ratio of the first-step stope was 1∶8，and the width of the second-step stope was 18meters based on the synthesized consideration of the safety，high efficiency and costs.

Key words: Stope structure parameters, Backfill ratio, Stability, FEM simulation