MANUFACTURING METHOD OF PRINTED WIRING BOARD

PROBLEM TO BE SOLVED: To provide a manufacturing method which enables the reduction of a film thickness of through hole lands and the formation of the flat through hole lands.SOLUTION: A manufacturing method of a printed wiring board includes the steps of: forming through holes 28 for through hole conductors on a departure substrate 20 formed by an insulation substrate; forming a seed layer 31 in the through holes and on a surface of the departure substrate; forming a plating resist 40 on a surface of the seed layer; forming an electrolytic plating film 36 on the seed layer exposed from the plating resist and filling the through holes for the through hole conductors with the electrolytic plating film; reducing a thickness of the electrolytic plating film; removing the plating resist; and removing the seed layer between the electrolytic plating films.