A superconducting magnet includes a superconducting coil, a coolant container, a radiation shield, a vacuum container, a first pipe, a refrigerator, a separator, a second pipe, a third pipe, a fourth pipe, and at least one pressure relief valve. The refrigerator is disposed such that a first flow path of vaporized coolant is defined by the refrigerator and the first pipe. The third pipe is connected to the first pipe outside the vacuum container, and extends in contact with the vacuum container. The fourth pipe is connected to the second pipe outside the vacuum container, and extends in contact with the vacuum container. The pressure relief valve is connected to the third pipe and the fourth pipe.