The invention relates to an interface portion substrate of a mechanical insert for a new energy vehicle. The interface portion substrate comprises a cylindrical cavity wrapping a copper bar electric connecting wire bar. An electric connection plug is vertically arranged at the intermediate position of the front end surface of the cylindrical cavity. The electric connection plug is arranged to extend forward along the cylindrical cavity. An anti-conductive elastic pressing member is disposed on the front end surface of the cylindrical cavity and around the electric connection plug. The anti-conductive elastic pressing member comprises groups of stacked elastic pressing rings which are successively connected one after another in the longitudinal direction of the electric connection plug. Thecenters of the groups of elastic pressing rings are located in the same axial line. The center of the vertical electric connection plug passes through the axial line. The front-end ring diameters ofthe groups of elastic pressure rings are successively reduced in the arrangement direction of the electric connection plug. When the anti-conductive elastic pressing member is in a natural state, theforemost elastic pressing ring extends in front of the electric connector plug, and the front-end diameter of the foremost elastic pressing ring is larger than the width of the electric connection plug. The front end of the foremost elastic pressing ring is provided with a soft magnetic ring.