Method of producing a wired circuit board

A method of producing a wired circuit board, the method including the steps of:

• a first step of providing an insulating layer having an opening penetrating in a thickness direction of the insulating layer at one side surface in a thickness direction of a metal plate,
• a second step of providing a first barrier layer at one side surface in the thickness direction of the metal plate exposed from the opening by plating, the first barrier layer being positioned at a lower end edge in the opening so as to take up only a portion of the opening in a thickness direction of the opening as compared to a thickness of the insulating layer,
• a third step of providing a second barrier layer continuously at one side in a thickness direction of the first barrier layer and an inner, side wall surface of the insulating layer which forms the opening,
• a fourth step of providing a conductor layer so as to contact the second barrier layer, and
• a fifth step of removing the metal plate by etching.