The classical digital speckle correlation method of deformation measurement is based on gray correlation between the images before and after deformation. In fact, this kind of images are fractal and its fractal dimension represents both gray and morph information. A fractal dimension correlation method of displacement measurement is developed. This new method fully takes the advantage of the correlation behavior of digital images, so, it could be more precise than the classical one. In order to verify validity of it, an experiment is designed. The result shows that its precision is better than 0.06 pixels.