The invention relates to a yellow soil-base sinter-strippable casting coating and a preparation method thereof. The casting coating comprises powder composed of yellow soil powder, lead zinc slag powder and bentonite at the weight ratio of (6-8):(2-4):(0.5-1.5), and silica sol which accounts for 3%-6% of the total weight of the powder. The preparation method comprises the following steps: firstly mixing the yellow soil powder with the lead zinc slag powder proportionally; roasting the mixed powder at the temperature of 800-1200 DEG C; adding the bentonite and the silica sol proportionally after the powder is cooled; and adding water for stirring to obtain the yellow soil-base sinter-strippable casting coating. The coating in the invention has good suspension property and can form strippable compact sinter skin after being cast; the obtained casting has the advantages of bright and clean surface, low roughness, high dimensional accuracy and good quality; and the preparation method has the advantages of simple process, low price and wide sources of raw materials, and good application prospect.