Abstract: According to the concrete features of Xiaoguanzhuang Iron Mine's ore body, the deep-middle deep hole sublevel-combined stoping with low preparation ratio and high mining intensity has been applied successfully in the first-ore seam mining. During practical production, the technical difficulties in drillng, explsivecharging equipment and high-speed cutting have been resolved to push on re forming the structure and technology of sublevel caving mining without floor pillars forward. This technique is avilable for other similar mines.