Abstract: Through the contrast experiments, the investigation on large spacing structure of non-pillar sublevel caving in Jinshandian Iron Mine is made to get reasonable parameters for recovering the crestal ore by non-dilution or low dilution.It is best of stopping mining when the mixed rate of gauges is 10% and the recovery rate is the highest.The experimental data shows that when the height of lift with the spacing of passage is 15cm×15cm, the recovery rate is high.Also, the height of crestal residual ore is in accord with the fixed value, which contributes to a good recovery at next sublevel.

Key words: Iron mine, Non-pillar sublevel caving, Large spacing, Crestal residual ore