The invention relates to the field of underground metal mine sublevel caving without floor pillar, and particularly relates to an adjustable automatic ore-drawing device which is controlled by PLC and is used for ore drawing experiments. The device comprises a linear guide rail, an ore drawing shovel and a guide mechanism. The upper part of the ore drawing shovel is connected with the linear guide rail. The lower part is connected with a guiding mechanism. The end part is connected with a pneumatic device. The PLC control system is connected with the pneumatic device through a circuit. The PLC control system enables the ore drawing shovel to carry out reciprocating linear motion along the linear guide rail on an ore drawing tunnel by controlling the pneumatic device; and under the joint action of the guiding mechanism, the ore drawing shovel automatically open and close at the bottom of a designated location. Continuous and automatic ore drawing is realized. The labor intensity of experiment people is reduced. The experiment efficiency is improved. The interference of human factors is removed. The experiment accuracy is improved.