PURPOSE: To manufacture a coil of metallic foil without causing defects by heat treatment such as annealing by coiling metallic foil around a metallic core with a thin film of combustion residue of a combustible in-between.

CONSTITUTION: A combustible layer 3 is formed around a metallic core 2, and metallic foil 4 is coiled around the core 2 with the layer 3 in-between to form a coil 1 of metallic foil. Paper, wood, cloth or the like is used as the constituent material of the layer 3. The coil 1 is heated to the annealing temp. in an electric furnace or the like. The layer 3 is burned by the heating, and a thin film 5 of combustion residue is formed on the surface of the core 2.