Abstract: In order to discuss the rationality of stope structure parameters of downward drift slicing and cementing fill mining method in Maoping lead-zinc mine，the stope stability at different drift section size and buried depth were calculated by the numerical simulation method，and the change rules of stress and plastic zones of backfill roof and stope surrounding were analyzed systematically.The results show that：with the increasing of drift span and buried depth，the tensile stress at stope surrounding rock also increases gradually.When the drift span reaches 5 m，the tensile stress is very close to tensile strength of backfill，and if the mining depth over 560 m，the tensile stress zone almost expands to the whole surrounding rock，which indicates that the stope stability has reduced，and the stope is likely to fail.From the calculation results，the maximum drift span should not exceed 5 m at the current mining depth（the depth is 400~450 m)，and if we continue to deep mining at 3.5 m drift span，the biggest mining depth should be less than 600 m.Otherwise，it is hard to ensure the stope stability.

Key words: Downward cementing fill, Stope stability, Stope structure parameter, Section optimization