A reusable collision energy absorption device for a rail vehicle, comprising an impact rod, an outer tube, a damping structure, a return structure and an end base, wherein the damping structure comprises a damping plug, a guide tube and a damping elastic element, and the return structure comprises a return piston and an elastic return element; the outer tube is in the form of a tubular structure, and an interior of the outer tube is partitioned into a front cavity and a rear cavity through a partition plate, the partition plate being provided with a damping hole in the form of a through hole, so that a damping fluid is able to circulate between the front cavity and the rear cavity; the impact rod comprises an impact end at a front end of the impact rod and a piston end at a rear end of the impact rod, the piston end of the impact rod being arranged inside the outer tube, and the impact end of the impact rod being arranged outside the outer tube; at least a portion of a length of the damping plug is arranged in the damping hole when the damping plug is in an initial position; the damping plug is movable in a front-rear direction of the device when the device is impacted, a rear end of the outer tube being fixedly connected to the end base so that the entire collision energy absorption device is able to be fixedly arranged on the rail vehicle, the rear cavity being provided with the guide tube, the damping elastic element, the return piston and the elastic return element, a front end of the guide tube being provided with a via hole through which a rear end of the damping plug is arranged inside the guide tube; a radial size of the rear end of the damping plug matches with an inner diameter of the guide tube so that the rear end of the damping plug is able to move frontward and rearward along an inner wall of the guide tube after the energy absorption device is impacted; and the return piston is fixedly connected to the end base through the elastic return element in the initial position; and the damping fluid is filled in a cavity between the rear end of the impact rod and a front end of the return piston, and a size of a radial thickest portion of the damping plug is smaller than a radial size of the damping hole, so that a gap is formed therebetween for the damping fluid to circulate between the front cavity and the rear cavity. wherein the damping structure comprises a damping plug, a guide tube and a damping elastic element, and the return structure comprises a return piston and an elastic return element; the outer tube is in the form of a tubular structure, and an interior of the outer tube is partitioned into a front cavity and a rear cavity through a partition plate, the partition plate being provided with a damping hole in the form of a through hole, so that a damping fluid is able to circulate between the front cavity and the rear cavity; the impact rod comprises an impact end at a front end of the impact rod and a piston end at a rear end of the impact rod, the piston end of the impact rod being arranged inside the outer tube, and the impact end of the impact rod being arranged outside the outer tube; at least a portion of a length of the damping plug is arranged in the damping hole when the damping plug is in an initial position; the damping plug is movable in a front-rear direction of the device when the device is impacted, a rear end of the outer tube being fixedly connected to the end base so that the entire collision energy absorption device is able to be fixedly arranged on the rail vehicle, the rear cavity being provided with the guide tube, the damping elastic element, the return piston and the elastic return element, a front end of the guide tube being provided with a via hole through which a rear end of the damping plug is arranged inside the guide tube; a radial size of the rear end of the damping plug matches with an inner diameter of the guide tube so that the rear end of the damping plug is able to move frontward and rearward along an inner wall of the guide tube after the energy absorption device is impacted; and the return piston is fixedly connected to the end base through the elastic return element in the initial position; and the damping fluid is filled in a cavity between the rear end of the impact rod and a front end of the return piston, and a size of a radial thickest portion of the damping plug is smaller than a radial size of the damping hole, so that a gap is formed therebetween for the damping fluid to circulate between the front cavity and the rear cavity.