To provide an efficient method to form a functional porous layer, a functional material being supported on a porous material such that the content of the functional material has a desired concentration distribution in the depth direction of the porous layer, a method to manufacture a fuel cell applying the above method to form a reacting layer and an electronic device and an automobile having the fuel cell manufactured by the method as a power supply. A method to form a functional porous layer including a functional material being supported on a porous material. The method includes applying a plurality of solutions or dispersions containing the functional material, the solutions or the dispersions having different surface tensions, to a porous layer to control the permeation of the functional material in the depth direction of the porous layer according to the difference in the surface tensions.