The invention relates to a concrete structure self-immune self-repairing microcapsule and a preparation method. The microcapsule is composed of a capsule wall and a core material in the capsule, the capsule wall is urea resin, and the core material is a mixture of ethyl phenylacetate and epoxy resin. Arabic gum solid, ammonium chloride solid, resorcinol and urea are weighed and dissolved in purified water, and a wall material solution is prepared; a core material solution is prepared from epoxy resin and ethyl phenylacetate; the wall material solution is adjusted to be acidic, the wall material solution is heated, the core material solution is added, stirring is carried out, a formaldehyde solution is added, the rotating speed is then adjusted to be 650 r / h-950 r / h, the temperature is keptat 55-85 DEG C, and stirring for 2-5 h is carried out; and the turbid liquid is cooled, suction filtration is carried out on the turbid liquid, purified water is added for washing, suction filtrationfor 3-4 times is carried out, and the filtrate is dried to obtain the product. The microcapsule prepared by the invention can ensure the service life of concrete to a great extent, effectively improves the corrosion resistance of the concrete, and can self-repair the cracking and shrinkage conditions of the concrete after being used for a certain time, thereby lowering the later maintenance cost.