A device and method for compensating dead pixels of an image includes estimating brightness changing trends at two sides of a dead pixel in image data and determining dead pixel brightness compensation values corresponding to the two sides of the dead pixel. Difference values between the brightness changing trends and between the dead pixel brightness compensation values at the two sides of the dead pixel along each predetermined direction is determined and a weighting factor corresponding to the difference values is determined. The dead pixel brightness compensation values corresponding to the two sides of the dead pixel along each predetermined direction are subjected to a weighting calculation based on the weighting factor to obtain a compensation result for the dead pixel.