Printed circuit board and method for manufacturing the same, and fuel cell

A conductor layer having a predetermined pattern is formed on a base insulating layer so that its second main surface opposes the base insulating layer. A barrier layer having higher corrosion resistance to acids than that of the conductor layer is formed on its first main surface and a side surface of the conductor layer while the first main surface and the side surface of the conductor layer and the barrier layer are covered with a conductive cover layer.