The invention provides a precise casting method of tiles of a floating wall of a combustion chamber of an aeroengine. The precise casting method of the tiles of the floating wall of the combustion chamber of the aeroengine comprises the following steps of: designing and manufacturing a model, lining sands, dewaxing, sintering, installing a mold shell, charging materials, sealing a pressure regulating device tank body, vacuumizing, smelting, regulating the intensity of pressure in a tank body, pouring, discharging the pressure, and cooling. According to the invention, main casting technology parameters are simplified into control vacuum level, gases are prevented from entering liquid metal in an atom or molecule type, and the defects of air holes, oxidation mixing in castings are reduced; the speed is pressurized, the pressure and the time are dwelled, the mold filling process of metal liquids can be controlled effectively through regulating the pressure and the pressurization speed during the pouring process, the technology parameters are controlled well; the mold filling capability of metal liquids is improved; the turbulent flow and splashing during the mold filling process are reduced, and the mixture formation is reduced; the mold filling and condensation processes of metal liquids are controlled, each performance of castings is improved, and the processing cycle is shortened.