In order to ensure the emission standards of coke oven flue gas, the concentration of sulfur dioxide in the flue gas must be controlled. A coke oven flue gas desulfurization technology solution by using magnesium oxide in the actual production was introduced. By implementing the desulfurization technology, the discharging of sulfur dioxide is less than 30 mg/m3 and the desulfurization efficiency is more than 95%; furthermore emissions of dust and nitrogen oxides could achieve the standards,thereby realizing a good economic and environmental benefits.