Coated catalysts have attracted much attention due to the urgent need of low-resistance technology for large-flow industrial flue gas purification. However, the complex characteristics of coating slurry and the factors influencing the loading for the catalyst preparation become a challenge. For the preparation of Cu-Mn based catalyst by vacuum coating on cordierite substrate, the influence of slurry characteristics (i.e., solid content, binder type, pH value and particle size) on the loading mass and adhesivity of catalyst was investigated. The results show that the increase of solid content makes the catalyst particles more closely bound to the network structure formed by thickener and silica sol, and improves the loading mass and adhesivity of the catalyst. Silica sol can effectively increase the electronegativity on the surfaces of the particles in the slurry, thus leading to the dispersion of the catalyst particles in the slurry. The increase of pH value reduces the zeta potential on the particle surface, reduces the slurry viscosity and improves the slurry stability. Grinding can destroy the uniform and stable network structure of the slurry, affecting the catalyst adhesivity negatively. A coated catalyst with a loading mass of 216 kg·m-3, a shedding rate of 0.6%, and a catalytic CO efficiency of greater than 98% (7 200 h-1, 120 ℃, 8% H2O) is obtained when an unground slurry with a silica sol content of 30% (in mass fraction), pH value of 7.3 and solid content of 30% (in mass fraction) is used.