The invention discloses a preparation process of a metal door and window coating with an anticorrosion function. The preparation process includes the step: firstly, weighing raw materials for standbyapplication, by weight, 34-40 parts of mixed resin, 6-10 parts of resin additives, 14-22 parts of anticorrosion reinforcing agents, 3-5 parts of polyethylene glycol, 2-4 parts of wax emulsion, 4-8 parts of nano-diatomite and 3-7 parts of rust-proof pigments. According to the preparation process of the metal door and window coating with the anticorrosion function, the coating is further researchedand developed, acid and alkali resistance is further improved, and the coating has a high use value and a good application prospect.