The invention relates to a low-temperature cooling system of a superconduction high-intensity magnetic field magnetron sputtering cathode. The low-temperature cooling system is composed of two liquid nitrogen storage Dewars (1 and 5), pressure increasing valves (2 and 6), deflation valves (3 and 7), a first liquid transmitting pipe (4-1), a first liquid transmitting rod (4-2), a second liquid transmitting pipe (8-1), a second liquid transmitting rod (8-2), a vacuum cavity (9), a magnetic body Dewar upper cover (10) and a magnetic body Dewar base (11). A superconducting magnetic body (12), an outer magnetic yoke (13), an inner magnetic yoke (14) and a bottom magnetic yoke (15) are installed in closed space defined by the magnetic body Dewar upper cover (10) and the magnetic body Dewar base (11), the magnetic body Dewar upper cover (10) and a cathode target material (16) are fixed together, and part of a vacuum gap (17) is reserved between the magnetic body Dewar upper cover (10) and the cathode target material (16). Forced flowed cooling is carried out on the superconducting magnetic body (12) through liquid nitrogen; the two liquid nitrogen storage Dewars (1 and 5) alternatively work to cool the superconducting magnetic body (12) and the cathode target material (16).