The invention relates to a decorative material and provides an energy-saving antibacterial lacquer and a preparation method thereof. The energy-saving antibacterial lacquer comprises the following raw materials in parts by weight: water, an emulsion, natural colored sand, alkyl glycoside, a phthalate plasticizer, a film forming additive, ammonium polyacrylate, a heat insulation additive, rhamnolipid and dodecyl dimethyl benzyl ammonium chloride. Alkyl glycoside used as a thickening agent to be compounded with the film forming additive is beneficial to the improvement of the plastic flowability and elastic deformation performances of the lacquer. Due to the addition of the heat insulation additive, the heat insulation property of the lacquer can be improved, and meanwhile, the use amounts of other raw materials in a coating can be reduced. The addition of rhamnolipid and dodecyl dimethyl benzyl ammonium chloride which are used as antibacterial agents is beneficial to the improvement of antibacterial property of the lacquer and the prolonging of the service life of the lacquer. By simply mixing the raw materials of the energy-saving antibacterial lacquer, the preparation method is simple in operation and easy to realize mass production.