The invention provides a pneumatic stirring and slurry mixing device and an application method thereof. The pneumatic stirring and slurry mixing device comprises a slurry mixing system and a pneumatic stirring system, wherein the slurry mixing system comprises a slurry mixing tank and a clean water tank which are communicated with each other a water inlet pipe; the water inlet pipe is provided with a water suction pump and a water inlet valve; the pneumatic stirring system comprises an air inlet pipe; one end of the air inlet pipe is connected with an air compression hole and the other end passes through the slurry mixing tank and extends to the bottom to be connected with a cuttlefish-shaped exhaust pipe. On one hand, a tank body is continuously supplied with air by compressed air, and the slurry in the tank body forms a turbulent flow state in a brownian motion form, so that the turbulent flow state has the advantages that a chemical material can be more easily dispersed and dissolved in a solvent in comparison with a conventional single eddy current flow state generated by driving a blade to rotate by an electric stirrer by virtue of a motor, the slurry at different positions among different layers is turbulently stirred and stirring is more uniform; and on the other hand, an electric shock hazard is avoided by pneumatic stirring, a risk of a mechanical rotation injury is avoided, so that the pneumatic stirring and slurry mixing device is higher in security than a conventional electric stirrer.