The high voltage component assembly includes a first high voltage component and a second high voltage component for operating respectively upon reception of high voltage supply from a supply source, a case body for containing the first high voltage component therein, a lid to be attached to the case body to prevent access to an inside of the case body in a state of the lid being attached to the case body, a fastening member to be fastened in a fastening state to fix the lid so as not to be detached from the case body, a receptacle to which the second high voltage component is attached, the receptacle being provided at a position precluding release of the fastening member from the fastening state in a state of the receptacle receiving the second high voltage component attached, and a cutoff device for cutting off the supply of the high voltage from the supply source upon detachment of the second high voltage component from the receptacle.