A mounting structure for a power conversion device includes: a vehicle body component extending in a front-rear direction of a vehicle; a mounting component provided on the vehicle body component; a drive unit held by the vehicle body component via the mounting component; and a power conversion device attached to the mounting component. A stiffness of the mounting component is greater than a stiffness of the vehicle body component. The power conversion device is arranged between a front end and a rear end of the drive unit in a side view of the vehicle.