The invention discloses a scene light source estimation accuracy improving method based on a camera response function. The method comprises the steps of calculating out a camera transfer matrix between a training image and a test image at first; then utilizing the matrix to convert the training image and a true light source of the training image into an image and a true light source under a camera which correspond to the test image; extracting characteristics of the converted image; learning a regression matrix between the characteristics and the true light source; finally utilizing the regression matrix to finish light source estimation of the test image and achieving the light source estimation between different image libraries. According to the method, any parameter is avoided, the transfer matrix between the cameras and the regression matrix between the characteristics of the training image and the light source can be determined by being calculated out once and can be directly applied to estimating light sources of images shot by the cameras used by the different training images, and the light source estimation accuracy between the different cameras can be effectively improved.