The invention provides a rapid cooling device and method of a die casting mold used for a high-silicon aluminum alloy cylinder body and is applicable to the technical field of automobile engines, aiming at solving the problem that cooling speeds of traditional water cooling and air cooling are relatively slow at present. The invention provides the rapid cooling device of the die casting mold used for the high-silicon aluminum alloy cylinder body; the device comprises an inner vacuumized metal round pipe, a working solution, a liquid absorption core, a heat dissipation device and a mold connecting device; the invention further provides the rapid cooling method of the rapid cooling device; a power source is not needed, and a physical phase change principle is used as a driving source for circulating; in a working process, other energy sources do not need; the cooling device and method, provided by the invention, can realize rapid cooling of an appointed position of the die casting mold; the cooling speed is several times than that of traditional water cooling and air cooling methods.