A substrate for a printed circuit board according to the present invention includes a base film having an insulating property and including at least one opening; a first conductive layer that is formed on both surfaces of the base film by applying and heat-treating a conductive ink containing metal particles, and that fills the at least one opening; and a second conductive layer formed, by plating, on at least one of surfaces of the first conductive layer. The metal particles preferably have a mean particle size of 1 nm or more and 500 nm or less.