The invention discloses a simple alcohol-based casting coating and a preparation method thereof and belongs to the field of casting coatings. The coating comprises the following components in parts by weight: 65-75 parts of zircon power, 1.5-4 parts of lithium-based bentonite, 1-2.5 parts of clay, 0.8-3.5 parts of resin, 5-10 parts of silica sol, 0.1-0.3 part of polyvinyl butyral and 45-55 parts of industrial alcohol. The coating preparation method sequentially comprises the following steps of: 1, weighing and grinding the zircon power, adding and grinding lithium-based bentonite, adding and grinding clay and silica sol, adding and grinding resin, wherein the powder is uniformly ground; and adding an additive polyvinyl butyral into the powder, and fully grinding to prepare dry powder; and 2, slowly adding alcohol into the dry powder, stirring to a proper concentration, and preparation the coating. The defects in the prior art are overcome, the coating has good effects on aspects of suspension, brushing property, high-temperature cracking resistance and burnt-on sand resistance, and the produced casting piece is excellent in surface quality; and moreover, the coating is simple and rapid in process, short in production cycle, high in production efficiency, low in cost and good in market prospect.