A mounting structure for an electric device of a vehicle includes a case body configured to accommodate the electric device inside the case body, at least one fixing portion provided continuously with the case body and configured to be fixed to a vehicle body of the vehicle, and at least one hollow portion disposed between the case body and the fixing portion. When a load from the vehicle body is transmitted to the fixing portion, the hollow portion is deformed and/or broken by the load so that the load can be absorbed. Thus, transmission of the load to the case body can be suppressed.