The invention relates to a preparation method of a low-resistance anti-corona material for a vacuum pressure impregnation insulation system. The preparation method comprises the steps that crylic acid or an acrylic acid copolymer is added in the polymerization stage of preparing polyacrylonitrile and carbon nanotube composite fibers; by utilizing wet spinning, precursor fibers and glass fibers are twisted into threads, the threads are woven into cloth, and the cloth is rolled and sheared to serve as the low-resistance anti-corona material. The low-resistance anti-corona material is half-lapped outside an insufficient-glue main insulation layer of a stator coil bar, the surface of the overall stator coil bar is coated with a layer of demoulding strips with holes, the stator coil bar is placed into a vacuum pressure paint impregnation tank, after being impregnated with paint, the stator coil bar is bound with a high-resistance anti-corona layer in a half-lapping mode and contained in a mould, the mould is placed in an oven, and hot-press solidification forming is performed; after the main insulation layer is formed through solidification, sharp corners on the arris surfaces of the coil bar are removed, a layer of anti-resistance anti-corona paint can be painted outside a protection layer, and then the finished product, VPI stator coil bar, is obtained. According to the preparation method, the problem that the impregnation paint is polluted due to the fact that conduction materials in an anti-corona layer fall off when vacuum paint impregnation is performed on the low-resistance anti-corona layer of the stator coil bar in the insufficient-glue insulation system is solved.