The application provides a desulfurizing agent. The desulfurizing agent is prepared from the ingredients in parts by mass: 1-20 parts of sulfide complexing agent, 30-90 parts of complex dispersant, 0.1-5 parts of antioxidant and 1-10 parts of antifoamer. Through adding the desulfurizing agent during rectifying, sulfides can be efficiently removed from MTBE (Methyl Tert-Butyl Ether), and the sulfur content of the product MTBE can be lower than 10ppm and reaches standards for national blended gasoline V; meanwhile, sulfides with relatively low boiling points are complexed to form a high-boiling-point ingredient, evaporated materials during rectifying are reduced, the heat consumption is lowered, and the effect of preventing tower-bottom heavy components from coking is achieved; the recovery rate of the MTBE can be increased by 1% to 3% compared with similar desulfurization technologies.