Method and system for fan control

The invention provides a method and system for fan control. The method includes the steps that a reliable temperature of each hard disk in operation is preset; a one-to-one corresponding relation between the average temperature of the hard disks and the rotating speed of a fan is established and stored and when the temperatures of the hard disks are higher than the reliable temperatures, a corresponding relation between the temperatures and the rotating speed of the fan is established and stored; actual temperatures of the multiple hard disks are read; the read actual temperatures of the multiple hard disks are sequentially compared with the preset reliable temperatures of the hard disks in operaiton, when no temperature of the hard disks is higher than the reliable temperatures of the hard disks in operaiton, the average temperature of the hard disks is calculated, the rotating speed, corresponding to the pre-stored average temperature, of the fan is found, and a control signal is output to the fan so that t