A wiring substrate with a lead pin is formed by bonding lead pins to electrode pads formed on a wiring substrate through conductive materials. In the lead pin, a conic protrusion part whose side surface is formed in a concave surface is formed in the end face side opposed to the electrode pad of a head part formed in one end of a shaft part. The lead pin is bonded to the electrode pad in a state in which the conductive material extends to the back surface side of a head part beyond a flange part of the head part and reaches the shaft part of the lead pin.