Abstract: In order to ensure the stable production of ultra-thick bed sintering and effectively suppress the deterioration of air permeability caused by the increase of the thickness of the material layer, the optimization scheme of air permeability of the material layer under the sintering production conditions of ultra-thick layer was explored through sintering cup experiments. The experimental results show that the particle size and strength of quasi-particles can be effectively adjusted by increasing the water distribution and lime activity. The granulation experiment results show that the average particle size of quasi-particles in dry sieve is increased from 2.81 mm to 3.51 mm, the compressive strength of quasi-particles is increased from 2.72 N to 4.72 N, and the temperature of quasi-particles is increased from 37.1 ℃ to 50.1 ℃ after optimization. Closer to the dew point temperature, effectively avoid the material layer wet phenomenon. The results of sintering cup experiments show that the average permeability index of the material layer is increased from 401.65 to 659.25, the yield is increased from 70.8% to 80.4%, and the drum index is increased from 65.0% to 71.1% after optimization. The overall sintering index is improved. Finally, according to the production equipment parameters of the enterprise, the dew point temperature of the sintering mixture should reach more than 52.56 ℃. After adjusting the sintering parameters based on the experimental results, the overall sintering production efficiency was significantly improved.