The invention relates to the field of coatings, and discloses a waterproof and fireproof coating and a preparation method thereof. The waterproof and fireproof coating is prepared from the following components in parts by weight: 40 to 50 parts of hydroxy acrylic resin, 15 to 20 parts of chlorinated polypropylene resin, 10 to 15 parts of butyl acetate, 0.4 to 0.8 part of flatting agent, 0.5 to 0.8 part of glycerol monostearate, 5 to 9 parts of iron oxide red, 10 to 15 parts of methylbenzene, 5 to 8 parts of titanium carbide, 2 to 5 parts of vinyltriethoxysilane, 5 to 9 parts of propylene glycol methyl ether acetate, and 6 to 9 parts of water repellent. The waterproof and fireproof coating has the advantages that the waterproof and fireproof properties are better, and the strength is higher.