A press separator made of a stainless steel sheet, for providing excellent corrosion resistance and electric conductivity by a combination of a passive coating and a deposition of boride or boron carbide, restriction corrosion without separation or coming-off, by press forming, of depositions, and ensuring an extended service. A stainless steel sheet, containing 0.005-1.5 wt. %, of B and having deposited on the surface thereof at least one kind out of M₂₃ (C, B)₆ type boron carbide, and M₂B type and MB type borides, is press-formed in a corrugated shape having continuous irregularities, with angles of bent portions formed by bending or unbending by press forming being set at at least 15 degrees and an outward bending R-value at up to 1 mm.