A metallic separator according to a first embodiment is formed by obtaining a blank by rolling a metallic material having conductive inclusions, and removing a surface of the blank by 2% or more of the thickness of the blank. A metallic separator according to a second embodiment is formed by pressing a metallic plate so as to have a cross section including ridges and grooves alternatively, and removing parts of the ridged portions so as to make flattened surfaces. A metallic separator having conductive inclusions in its metal texture according to a third embodiment is formed by blasting a liquid containing two or more kinds of abrasives having different particle diameters to a blank after it has been rolled. A metallic separator having conductive inclusion in its metal texture according to a fourth embodiment is formed by blasting a passivation treatment liquid mixed with abrasives to the separator.