The invention relates to nanometer external wall panel coating and a thermal insulating external wall panel. The thermal insulating external wall panel comprises an insulation board, wherein a plurality of ventilation holes penetrating the thickness of the insulation board are formed in the insulation board at intervals; the diameter of an end towards the exterior of each ventilation hole is large, and the diameter of an end towards the interior of each ventilation hole is small. When a thermal gas flow suddenly meets the situation that a gas flow channel becomes narrower, as the air pressureis suddenly increased, the temperature can be decreased; when all the insulation boards are adopted on the side wall of a room, external hot air is supplemented to the interior from the ventilation holes, as the diameter of an end of the ventilation hole is small and the diameter of an end is small, and hot air is compressed when passing through the ventilation holes, the air temperature can be decreased; secondly, when external damp air passes through the ventilation holes, water in the air can be partially separated out and adhered to the inner walls of the ventilation holes during the compression of the air, so that the humidity of the air supplemented to a room from the ventilation holes is reduced, and the temperature is reduced, so that the effect of energy conservation is achieved.