Abstract: The stability of cemented backfill is crucial to the efficient mining of metal mines.Accordingly，the numerical simulation method is used to set up the reasonable physical parameters and mechanical parameters，which are based on the actual structure of the stope.Then，simulating and analysing the deep X₁ orebody in zijinshan Gold copper mine.Eighteen monitoring points have layouted in the rooms and pillars to record the deformation characteristics when the rooms and pillars are firstly and secondly excavated and filled.According to the stress distribution，plastic zone distribution and displacement variation，both the stability of stope can be determined and the process of backfill stability can be analyzed.