The invention relates to an assembled blade guniting stirring drill bit and a using method thereof. The drill bit is composed of a hexagonal male joint, a drill rod body, an upper guniting opening, a clamping plate, a bolt, assembled blades, an auxiliary clamping plate, a nut, a core pipe, a lower guniting opening, a sealing gasket, guniting blade assemblies, an air spraying opening and a drill tip, wherein the hexagonal male joint is welded to the top end of the drill rod body, the guniting blade assemblies are arranged at the upper end and the lower end of the drill rod body, the multiple assembled blades are arranged at intervals in the period, and the drill rod body is provided with the upper guniting opening, the lower guniting opening and the air spraying opening. The problems that the guniting amount of the edge area of a large-diameter stirring pile is insufficient, and stirring is not uniform are effectively solved, the integrity of a pile body of the stirring pile is remarkably improved, the pile forming quality is good, and safety and reliability are achieved.