The invention relates to the field of pool coatings, and specifically discloses a single-atom algicidal and bactericidal pool coating and a preparation method thereof. A single-atomic algae-killing and sterilizing pool coating, comprising raw materials in the following proportions: the product contains the following components in weight percentages: 20-30% deionized water, 2.0-3.0% dispersant, 0.2-1.0% defoamer, propylene glycol 1.5-2.5%, filler 20-35%, thickener 1.0-2.0%, film-forming aid 1.0-3.0%, ultra-fine styrene-acrylic emulsion 35-45%, pH regulator 0.1-0.5%, single-atom algicide Bactericide 1.0‑8.0%; its preparation method is: first add deionized water, add dispersant, defoamer, propylene glycol, filler, single atom algicide and bactericide under stirring, stir, grind, then add thickener, Deionized water, film-forming aids, ultra-fine styrene-acrylic emulsion, defoamer, and pH regulator are stirred to obtain a finished product. The invention is applied to the pool coating, and has the advantages of algae killing and anti-algae, antibacterial and anti-virus, and long-lasting purification.