A mounting structure of a high voltage unit for an electric vehicle, comprising: an electric motor as a first high voltage unit, used as a drive source of the vehicle, which first unit has two vehicle body fixing parts to be fixed to a vehicle body at both ends in a width direction of the vehicle when viewed from the front side of the vehicle; and an inverter as a second high voltage unit configured to control the drive of the electric motor, which second unit is arranged on an upper side of the first high voltage unit in a vertical direction of the vehicle, wherein: the first high voltage unit is provided with a concave part on a surface on the upper side in the vertical direction of the vehicle; the second high voltage unit is provided with a convex part on a surface on a lower side in the vertical direction of the vehicle, wherein a high voltage heavy component (7, 8), included in the second high voltage unit, is arranged within the convex part; and the first high voltage unit and the second high voltage unit are integrally formed while the convex part of the second high voltage unit is received in the concave part of the first high voltage unit, and the second high voltage unit is fixed to the vehicle through the two vehicle body parts of the first high voltage unit, such that at a time of a collision at the front of the vehicle, the first and second high voltage units (1,2) rotate towards the front of the vehicle according an inertial force around the rotation axis connecting the two vehicle body fixing parts, wherein the two vehicle body fixing parts are arranged at the bottom of the first high voltage unit. an electric motor as a first high voltage unit, used as a drive source of the vehicle, which first unit has two vehicle body fixing parts to be fixed to a vehicle body at both ends in a width direction of the vehicle when viewed from the front side of the vehicle; and an inverter as a second high voltage unit configured to control the drive of the electric motor, which second unit is arranged on an upper side of the first high voltage unit in a vertical direction of the vehicle, wherein: the first high voltage unit is provided with a concave part on a surface on the upper side in the vertical direction of the vehicle; the second high voltage unit is provided with a convex part on a surface on a lower side in the vertical direction of the vehicle, wherein a high voltage heavy component (7, 8), included in the second high voltage unit, is arranged within the convex part; and the first high voltage unit and the second high voltage unit are integrally formed while the convex part of the second high voltage unit is received in the concave part of the first high voltage unit, and the second high voltage unit is fixed to the vehicle through the two vehicle body parts of the first high voltage unit, such that at a time of a collision at the front of the vehicle, the first and second high voltage units (1,2) rotate towards the front of the vehicle according an inertial force around the rotation axis connecting the two vehicle body fixing parts, wherein the two vehicle body fixing parts are arranged at the bottom of the first high voltage unit. the first high voltage unit is provided with a concave part on a surface on the upper side in the vertical direction of the vehicle; the second high voltage unit is provided with a convex part on a surface on a lower side in the vertical direction of the vehicle, wherein a high voltage heavy component (7, 8), included in the second high voltage unit, is arranged within the convex part; and the first high voltage unit and the second high voltage unit are integrally formed while the convex part of the second high voltage unit is received in the concave part of the first high voltage unit, and the second high voltage unit is fixed to the vehicle through the two vehicle body parts of the first high voltage unit, such that at a time of a collision at the front of the vehicle, the first and second high voltage units (1,2) rotate towards the front of the vehicle according an inertial force around the rotation axis connecting the two vehicle body fixing parts, wherein the two vehicle body fixing parts are arranged at the bottom of the first high voltage unit.