The invention discloses a water-based plastic 
coating. The water-based plastic 
coating comprises the following components: a water-based resin 
emulsion, deionized water, a filler and additives. The invention further designs a preparation method of the water-based plastic 
coating, and the preparation method comprises the following steps: adding the filler into the water-based resin 
emulsion, adding an appropriate amount of deionized water, stirring, pouring into a sand mill for 
grinding, putting into a dispersing cylinder when the 
fineness is below 80mu m, adding the additives, sealing, stirring and detecting the 
viscosity for not less than 95s to prepare the water-based plastic coating. The water-based plastic coating has excellent water absorption, 
water retention, water suction and drainage and a good 
humidity adjusting effect, can be used for regulating the indoor 
relative humidity, and has the advantages of relatively high scrubbing resistance, 
water resistance and 
solvent resistance, 
corrosion resistance, alkali resistance, light resistance, 
weather resistance, good film-forming property, excellent color retention, 
wear resistance, 
corrosion resistance, controllable 
hardness, high performance-
price ratio and the like, and the preparation method is simple, easy to operate without 
pollution, good in construction and safe to use.