Abstract: At present, the large-sized drilling and LHD equipments are widely used in sublevel caving(SLC) and the cross dimension of sublevel drift is further enlarged with the mechanization. In this paper, the author set up the flowing velocity distribution formulas at the drawing outlet in SLC according to the characteristic pattern of blasted ores, and uncovered the influence mechanics to ore drawing in SLC by taking into consideration of the effective flowing section towards the drift, the drift width and loading manner. It was pointed out that in order to reduce the dilution and the ore loss in discharging operation in SLC the loading depth of LHD should be augmented and the full face even-drawing style should be executed as much as possible so that the ore-rock interface moves downwards as plat as possible.