The utility model discloses a composite waterproof insulation construction and heater, composite waterproof insulation construction is including the relative fire -retardant board that sets up, setting two polyurethane fiber layer, setting between the fire -retardant board are in polyurethane fiber layer relative two high temperature flameproof fibre layer and setting up on the surface is in waterproof coating on the high temperature flameproof fibre layer. The utility model discloses a multilayer structure such as polyurethane fiber layer, waterproof coating cooperation forms composite waterproof insulation construction, and the cladding is in departments such as the heater terminal box outsides, plays real heat preservation to the heater, especially the condition such as water droplet, ponding appear in the heater terminal box on preventing the heater, guarantees the insulating properties of heater.