A power coupling device for a hybrid electric vehicle comprises a flange shaft equipped with a shaft body and a flange disc and provided with an annular accommodating groove, a rotor flange rotationally covering the shaft body and fixed in an axial direction and provided with a hollow shaft, an axial end of which extends into the accommodating groove and the other end of which is fixedly provided with a flange part in an axial direction and arranged opposite to the flange disc, a counter-pressing disc capable of rotating surrounding an axle wire and being fixed in an axial direction, and a first and second spacing members, wherein the first spacing member is disposed in the hollow shaft and axially abutted against the flange part and the flange disc in an axial interval between the flange part and the flange disc; the counter-pressing disc is provided with an annular groove axially facing the flange disc; the groove winds the axle wire; the groove and the flange part are arranged on different sides of the flange disc; the second spacing member is disposed in the groove and axially abutted against the flange disc and the counter-pressing disc.