A passivation surface treatment method of stainless steel that improves corrosion resistance including in a brine environment without changing the appearance of the surface of stainless steel. A passivation surface treatment method for stainless steel includes: performing degreasing of stainless steel, performing electrolytic pickling where the stainless steel that underwent the degreasing is immersed in a pickling solution having phosphoric acid (H3PO4) and is connected to the anode and a voltage of about 0.5 to 5.0 V for about 10 seconds or more is applied, performing electrolytic degreasing of the stainless steel, and performing electrolytic passivation where the stainless steel that underwent the electrolytic degreasing is immersed in a passivation solution including dichromic acid and chromium sulfate and a voltage of about 0.5 to 5.0 V is applied for 5 seconds or more.