The invention provides a color temperature determination method and device. The method comprises the following steps: making a statistic of white balance gain of any two primary colors of the primary colors of an image of a target gray object which is collected under at least three target light sources of different color temperatures, and determining a relation curve of the white balance gain and the color temperature, wherein the target light source is a light source which satisfies black-body radiation; mapping an other related color temperature line in an CIE chromaticity diagram to the relation curve of the white balance gain and the color temperature, so as to calibrate an other related color temperature line of a color temperature corresponding to the image of the target gray object collected under each target light source; and determining a color temperature of an image to be detected according to the white balance gain of the image to be detected and the other related color temperature line. By adopting the embodiment of the invention, the applicability and accuracy of color temperature determination can be improved.