Disclosed are a white balance device and a white balance method. The device comprises a unit used to extract background pixels of an image; a unit used to obtain representative color of background; a unit for determining a global magnification ratio of the background pixels; a unit used to carry out pre-adjustment with regard to original color of each of the background pixels; a unit used to, for each of the background pixels, determine expected final background color of the corresponding background pixel, and then determine an accurate magnification ratio of the corresponding background pixel; and a unit used to, for each of the background pixels, carry out adjustment with regard to the original color of the corresponding background pixel by using the accurate magnification ratio of the corresponding background pixel.