There is provided a method of manufacturing a wiring board, including the steps of: preparing an insulating layer 1a including a cavity formation region X, and a separable metallic foil M formed of first and second metallic foils M1 and M2; allowing the separable metallic foil M to adhere to at least a lower face side of the insulating layer 1a with the first metallic foil M1 serving as an adhering surface; forming a cavity 2 by digging the insulating layer 1a and the separable metallic foil M in a cavity formation region X from an upper surface side of the insulating layer 1a to a depth that does not penetrate the second metallic foil M2; inserting an electronic component D into the cavity 2, and fixing the electronic component D by a fixing resin J; and peeling off the second metallic foil M2.