Activated carbon could efficiently remove sulfur dioxide in sintering flue gas, but it was also affected by the process parameters of the adsorption tower. In order to reveal the influence of process parameters on the desulfurization rate, the variable control method was used to study the activated carbon desulfurization by simulating sintering flue gas. The results showed that the airspeed, humidity, oxygen content of the flue gas and the temperature of activated carbon bed had great effects on the desulfurization performances. While the particle size of activated carbon had little effect on the desulfurization rate. With reducing the airspeed, activated carbon bed temperature and activated carbon size, the desulfurization rate increased because of the improvement of the SO2 physisorption. Moreover, the desulfurization rate could be increased by increasing the humidity and oxygen content of the flue gas, which promoted the SO2 chemisorption. However, when the humidity of the flue gas was over 12%, the water vapor aggregated on the activated carbon to form a water film, resulting in a decrease in the desulfurization rate.