Abstract: Wushan Copper Mine want to replace hydraulic sand filling method with underhand cut -and -fill stoping for its high production.The phaseⅠtrials results show that underhand cut-and-fill stoping is technically feasible.but there are still a series of problems.Optimizing back filling system, e.g.vibration sieve, filling batching, drain system etc, is studied on phase Ⅱ trials.It has been found that the results provide great guidance in similar mines.