The invention discloses a freight train bulk material compacting and flattening device. The freight train bulk material compacting and flattening device comprises a hydraulic cylinder, a pump station, a support, a compacting wheel and a movable frame. The pump station is connected with the hydraulic cylinder. The support is fixedly connected to the ground. One end of the movable frame is hinged to the support, and the other end of the movable frame is rotationally connected with the compacting wheel. The movable frame is provided with a hydraulic cylinder connecting end. One end of the hydraulic cylinder is hinged to the corresponding position of the support above the movable frame, and the other end of the hydraulic cylinder is connected with the hydraulic cylinder connecting end on the movable frame, and the acute angle is kept between the movable frame and the horizontal direction. A flattening plate is further arranged in front of the compacting wheel. The support is further provided with a retaining device used for bearing the weight of the compacting wheel and the movable frame after compacting is over. In the freight train bulk material compacting and flattening device, the acute angle is set between the movable frame and the horizontal plane, so that the stress condition of the whole compacting device is greatly improved, and the compacting effect is improved; and the freight train bulk material compacting and flattening device is simple and reasonable in structure and easy to operate.