Fan control method and device

The invention provides a fan control method and a device, wherein the method is used for controlling a fan sequence to radiate heat of a slot position sequence; the fan sequence comprises a plurality of fans; the slot position sequence comprises a plurality of slot positions; each slot position in the slot position sequence at least corresponds to one fan in the fan sequence; the method comprisessteps of: a fan control device determines a slot position collection which is the collection formed by the slot positions occupied by single plates to be irradiated; the fan control device acquires afan collection according to the corresponding relation between the slot position and the fan; the fan collection is the collection formed by the fans which correspond to the slot positions in the slot position collection; and the fan control device controls the rotating speed of the fans in the fan collection according to the temperature of the single plates and a fan rotating speed control arithmetic. The embodiment of the invention can ensure the heat dissipation effect of the single plates.