The invention discloses an anti-yellowing terrace coating and a construction method thereof. The anti-yellowing terrace coating is prepared from the following raw materials in parts by weight: 50-60 parts of polyurethane, 60-70 parts of rosin water, 15-25 parts of butyl acetate, 15-20 parts of propylene glycol 1-monomethyl ether 2-acetate, 8-15 parts of sodium polyacrylate, 5-10 parts of sodium dehydroacetate, 5-8 parts of xylene, 5-10 parts of tributyl tin chloride, 3-5 parts of benzophenone and 1-3 parts of nipalgin; the construction method of the anti-yellowing terrace coating sequentially comprises the following steps: polishing with abrasive paper, dedusting, puttying, rubbing down a wall surface, roll-painting a thin layer of anti-yellowing terrace coating, airing, roll-painting a second layer of anti-yellowing terrace coating, carrying out roll-painting finishing and naturally airing. The anti-yellowing terrace coating is excellent in anti-yellowing property and is still purely white after being painted for multiple years.