A superconducting magnet assembly includes a bobbin comprising a central bore along a longitudinal direction, and a superconducting coil package wound on the bobbin. The superconducting coil package includes a plurality of superconducting coil layers wound on the bobbin, a plurality of supporting member layers, each of the supporting member layers being between a corresponding two adjacent superconducting coil layers, and a thermal conduction layer between two superconducting coil layers or between a superconducting coil layer and an adjacent supporting member layer.