The invention provides a device and method for preparing spherical metal powder based on a uniform droplet one-by-one atomization method. The device comprises a shell, a crucible arranged in the shell, and a collection bin. The device is characterized in that a rotating disc arranged in a powder collection area is of an inlaid structure; a material with the poor heat conduction property is selected as a base body part of the rotating disc; a metal material is selected to be inlaid into a main part to serve as the atomization plane of the rotating disc, wherein the wetting angle between the metal material and droplets is smaller than 90 degrees; a concentric circular groove is formed in the atomization plane; and ventilation holes are formed in the rotating disc. The invention further discloses the preparation method. Combined with pulse micropore injection and centrifugal atomization methods, matched with the rotating disc structure, the surface of the rotating disc is subjected to induction heating, thus metal liquid breaks through the splitting mode of traditional molten metal, the fibrous splitting mode which can be achieved only when an atomized medium is an aqueous solution oran organic solution is achieved, the high-melting-point metal powder meeting the requirements is prepared, the particle size is controllable, the spherical degree is high, satellite droplets are avoided, the flowing spread performance is good, and the device is suitable for industrial production.