A color tone correction system includes a reception unit that receives a target workpiece image and design information of a target workpiece, a reference image data storage unit that stores a reference workpiece image, an image determination unit that determines whether or not the target workpiece is inclined more than the reference workpiece, a calculation processing unit that estimates an inclination angle of the target workpiece based on the stored reference workpiece image and the target workpiece image, a color tone data storage unit that stores a relationship between the inclination angle and a color tone correction value, an image correction unit that corrects a color tone of the target workpiece image based on the estimated inclination angle and a color tone correction formula corresponding to the stored relationship, and an output unit that outputs the corrected target workpiece image.