Abstract: The assembling of the magnetization-demagnetization coil of the CM2 laboratory developed by Beijing Institute of Spacecraft Environment Engineering is involves very complex operations and takes a long time. To solve this problem, this paper proposes a design of the magnetization-demagnetization coil with no connectors, based on a new circuit, with which it becomes very easy to assemble and it takes a very short time. Theoretical calculation indicates that the separated magnetization-demagnetization coil is equivalent to the CM2 one in its operation, as shown by a simulation analysis of the magnetic field.