Abstract: Objectives To establish a fading spectrophotometry by using potassium permanganate to react with sulfur sodium hydride in the air of workplace. Methods The sodium hydrosulfide in the air was collected with micropore filter membrane, after elution and oscillation with 10 mL water, 5mL of eluent was added to 5mL of 1.2mmol/L acidic potassium permanganate, the degree of fading was compared with standard series. Results The detection limit of the method was 9.5μg/m3, the linearity was in the range of 0~90μg, r =-0.9995, RSD=0.23%~1.93%, the recovery was in the range of 99.2%~100.7%. Conclusions The method was simple, accurate and sensitive and less in interference, which could meet the requirements for testing sodium hydrosulfide in the air of workplace.