Abstract Japanese maglev system consists of on-board superconducting magnets(SCMs) and ground coils. When SCMs vibrate due to magnetic fluctuation from ground coils, the heat load of SCMs increases not a little. To estimate this heat load of SCMs with different structures, we have done electromagnetic vibration tests by changing the inner structures of the SCMs. And then, we have tried to measure the eddy current on the inner vessel, and we got available knowledge. As a result, we have found that the increase of the heat load is influenced by vibration characteristics and resistivity of structures.