Abstract: Based on the ellipsoid theory and combining with the arrangement of the ellipsoid，6 stope structure parameters are designed in stage -430 m ~ -500 m at west section of Chengchao Iron Mine，and numerical simulation on 6 models of stope structural parameters under the same ore reserves are made by PFC.According to the results of simulation analysis，the ore recovery rate and dilution rate under 6 stope structure parameters are contrasted.The results show:under the same segment height，the recovery rates of large-space models and high-range models are higher than that of traditional models，and the dilution rates are lower than that in traditional models; With segment height increasing，the recovery rates of the three models will be reduced，but the overall dilution rates will be also lowered.The cost analysis model is established with recovery rate and dilution rate as cost impact indicators in caving production.Based on this model，the ultimate profits of 6 models with stope structural parameters are calculated，and the results show:the profit of large-space model is the highest under the same segment height; the total cost is reduced and the profit is increased in one kind of model as the segment height increases; The stope structural parameter model with segment height of 23.3 m，route space of 25m has the highest economic benefits.

Key words: Chengchao iron ore, Ellipsoid theory, Numerical simulation of ore drawing, Cost analysis model, Economic benefits