A motor unit according to an aspect of the present invention includes: a motor having a rotor that rotates about a motor axis and a stator located radially outside the rotor; an inverter that controls a current to be supplied to the motor; and a housing having a motor housing portion that houses the motor and an inverter housing portion that houses the inverter. The housing further includes an inverter housing provided with a top plate portion covering an opening of the inverter housing portion. The inverter is fixed to a back surface of the top plate portion, facing the inside of the inverter housing portion.