The invention discloses an eight-row-ball slideway device provided with a self-locking device, which comprises an outer frame, a middle frame and an inner frame. The middle frame is slidably arranged on the outer frame, the inner frame is slidably arranged on the middle frame, and the self-locking device is fixed on the outer frame and comprises a spring fixing arm and a sliding groove arm. The spring fixing arm and the sliding groove arm are connected integrally and communicated, a sliding block is slidably arranged in the sliding groove arm, a spring clamping groove is arranged under the sliding block, and a spring is arranged inside the spring fixing arm. One end of the spring is fixed at one end of the spring fixing arm away from the sliding groove arm, and the other end of the spring is fixed in the spring clamping groove of the sliding block. A protruding block is arranged above the sliding block, a clamping foot clamping groove is arranged on the protruding block, a clamping claw is fixed on the inner frame, and a clamping foot protrudes out of the clamping claw and arranged inside the clamping foot clamping groove. The slideway device can be withdrawn and locked automatically under the action of the self-locking device, and the situation that the slideway device is opened automatically without man-made external force is avoided.