The invention discloses a cathode structure of an aluminium cell, which belongs to the technical field of aluminium cells and comprises a cell shell and a lining, wherein the lining comprises a cathode carbon block, a lateral lining, a bottom lining and a tamping paste. The invention is characterized in that the cathode carbon block in the same aluminium cell is formed by arranging high cathode carbon blocks and low cathode carbon blocks, thereby enabling the upper surface of the cathode to be rugged; a cathode steel bar is horizontally arranged on the bottom of the cathode carbon block and passes through out of the lateral of the aluminium cell. Consequently, aluminium liquid is divided into a plurality of small aluminium ponds, thereby effectively restricting the flow and the fluctuation of the aluminium liquid due to the action of an electromagnetic force, improving the stability of the aluminium cell, reducing the height and the polar distance of the aluminium liquid, improving the current efficiency and achieving the goal of energy saving and consumption reducing.