To provide a dampproof composite material to which a dampproof property is given by coating various materials with a coating liquid comprising shellac and wax and conducting a proper heat treatment.

The dampproof coating liquid has shellac and wax as its main components. The dampproof composition material is obtained by coating a substrate with this dampproof coating liquid. A heat treatment at the temperature not less than 90°C for not less than 5 s is carried out to provide a dampproof property. The dampproof composition material is obtained by laminating a dampproof composition layer whose main components are shellac and wax on a substrate. The ratio (A/B) of the vapor permeability (A) of the substrate and the vapor permeability (B) of the dampproof composition material is not less than 8 or the vapor permeability of the dampproof composition material is not more than 50 g/m2×day.