The object of the present invention is to provide a sheet having an excellent heat resistance. The heat resistant sheet of the present invention is prepared by forming a phenolic resin film(s) on one or both sides of a thermoplastic resin sheet. The phenolic resin film(s) can be formed by coating a phenolic resin water solution into which a water soluble polymer has been added onto one or both sides of the thermoplastic sheet, and then heating.