The invention discloses an electric heating film and a preparation method and an application thereof. The electric heating film comprises a waterproof layer, an insulating layer, an electric heating layer, an electrode, an insulating layer, a thermal insulation layer and a waterproof layer and the like; the electric heating layer comprises fiber base fabric, a high-conductivity nanometer carbon material and a functional auxiliary; and the high-conductivity nanometer carbon material is adsorbed on the surface or in the gap of the fiber base fabric. The preparation method comprises the steps oftaking the fiber base fabric as the bearing substrate of the high-conductivity nanometer carbon material, performing wetting to form a hydrophilic treatment liquid firstly, next, performing baking andcuring, then coating with a wetted nanometer carbon aqueous dispersion liquid, and next, performing baking and curing to obtain the electric heating layer; and next, gluing with the insulating layer,the thermal insulation layer, the waterproof layer and the electrode through hot melt adhesive to form the electric heating film. The electric heating film is free of binder resin, so that the problem of electric heating performance degradation caused by resin aging can be obviously avoided; and the electric heating film has the integrated performance of electric heating, waterproof property, thermal insulation, reflection and the like, and can be widely applied to the industries of home heating, floor heating, thermal insulation, industrial heating and the like.