The invention relates to a self-discharging type coal mine hopper car, wherein the shape of a bottom plate of a coal hopper frame is a triangle; two sides of the coal hopper frame are provided with coal hopper doors; and the coal hopper frame is connected with the coal hopper doors through hinges. The two ends of the bottoms of the coal hopper doors are provided with circular shafts; the lower parts of the front and the rear walls of the coal hopper frame are provided with a bracket respectively; each bracket is provided with two straight bars; hooks at the lower end of a door-locking rod arematched with the circular shafts; the upper end of the door-locking rod is sleeved with one end of a connecting bar through a screw bolt; the door-locking rod is sleeved on a stay bar; two ends of the stay bar are fixed with the coal hopper frame and the straight bars through welding; two ends of the circular shafts respectively penetrate the front and the rear walls of the coal hopper frame and are sleeved with one end of another connecting bar and an operating rod; and the two connecting bars are sleeved through a screw rod. A bolt base is welded on the coal hopper frame and the coal hopperdoors after sleeving a bolt.