A high-pressure water jet cleaning device for sandblasting and descaling plate strip material, a cleaning line and a system. The cleaning device comprises cleaning tanks (7), rinsing tanks (18), and descaling nozzles (6), wherein the descaling nozzles (6) face the same width direction as plate strip material (5) and are arranged in a gradient along the transport direction of the cleaning tanks (7) so as to provide spray coverage of the plate strip material (5). The foregoing system comprises a cleaning device, abrasive material collection tanks (24), a high-pressure water supply system, an abrasive material supply, recovery, and sorting system, and a waste water circulation and treatment system.