At different temperatures, the zinc and aluminum infiltration agent was first dried, and then the sherardizing process was treated for Q235 steel, and the properties of the coating morphology, thickness, microhardness and roughness were recorded and analyzed by metallographic microscopy, microhardness meter, roughness meter and other instruments. Experimental studies were found that when the drying temperature changes in the range of 150~ 400 ℃, the topography, thickness, hardness, roughness and degree of seepage agglomeration of the coating showed a trend of first increasing and then decreasing. When the drying temperature was 300 °C, the macroscopic surface of the obtained coating was smooth and silvery-white, the microscopic particle arrangement was compact and dense, and the coating thickness, hardness and roughness were ideal.