The production method of the multifunctional exterior wall anti-crack putty provided by the invention is prepared in parts by weight, consisting of 13-17 parts of tap water, 0.18-0.22 parts of cellulose, 9-11 parts of pure acrylic elastic emulsion, and 18-18 parts of silicon acrylic elastic emulsion. 22 parts, 0.2-0.3 parts of defoamer, 1-2 parts of preservative, 0.8-1.2 parts of thickener, 28-32 parts of white cement, 6-9 parts of heavy calcium carbonate, 15-19 parts of quartz powder; Among them, the best preparation: 15 parts of tap water, 0.2 parts of cellulose, 10 parts of pure acrylic elastic emulsion, 20 parts of silicon acrylic elastic emulsion, 0.3 parts of defoamer, 1.5 parts of preservative, 1.0 part of thickener, 30 parts of white cement , 8 parts of heavy calcium carbonate, 17 parts of quartz powder; synthesized in a reactor, put into tap water, cellulose, silicon acrylic elastic emulsion, pure acrylic elastic emulsion, defoamer, preservative, thickener successively, and fully stir for 13- After 17 minutes, add white cement, heavy calcium carbonate, and quartz powder, stir for 40-50 minutes until uniform, wait for 10 minutes, visually observe that it reaches the required consistency, and use it. The particle size of heavy calcium carbonate is 750-800 mesh; the particle size of quartz powder is 260-300 mesh.