The invention provides a uniform mixing device for reagent tray magnetic beads as well as a use method. The device comprises an outer tray, wherein a first gear is arranged at the bottom of the outertray, a plurality of uniform mixing seats are arranged on the outer tray, second gears are connected with the uniform mixing seats, the second gears are meshed with the first gear, a third gear is meshed with the first gear, and a first driving device is connected with the third gear. The third gear is driven to rotate by the first driving device, the first gear is driven to rotate by the third gear, the uniform mixing seats are driven to rotate by the first gear, and a reagent mixed with magnetic beads is placed in the uniform mixing seats. When the magnetic beads are required to be uniformlymixed, only the first driving device is required to start, and the uniform mixing seats can rotate independently to uniformly mix the magnetic beads. The first gear drives the plurality of the secondgears to simultaneously rotate so as to drive the uniform mixing seats to rotate, the uniform mixing of the magnetic beads can be realized, the outer tray is not required to realize the uniform mixing of the magnetic beads, the experiment time is shortened, the rotation of the outer tray is reduced, so that wear of each component is reduced.