The invention relates to a device for preparing foamed aluminum through an air blowing method. The device for preparing the foamed aluminum through the air blowing method comprises an air blowing pipe, an air blowing head, a direct-current vibrating motor and a movement limiting plate, wherein the air blowing pipe comprises a horizontal section and a vertical section connected with the horizontal section; the horizontal section comprises an air inlet end; the vertical section comprises an air outlet end; the air outlet end is connected with the air blowing head; the air blowing pipe is of a cantilever beam structure; the air inlet end is the fixed end of the cantilever beam structure; the air outlet end is the free end of the cantilever beam structure; the direct-current vibrating motor and the movement limiting plate are fixedly arranged at the horizontal section of the air blowing pipe; moreover, the direct-current vibrating motor is arranged between the fixed end and the movement limiting plate; and the movement limiting plate can be used for limiting the movement, in the vertical direction, of the air blowing pipe. The invention also relates to a preparation method of the foamed aluminum.