Abstract: Phantom is widely used to evaluate CT image quality objectively. Currently, only DIGIDENT Phantom is exclusively used in evaluating image performance of Dental CT. This phantom was recommended by "YY/T 0795-2010 Particular specification for oral cavity X-ray equipment for digital tomography". Although most of image parameters can be tested by this phantom, there are still disadvantages with it. For example, no module for slice thickness measurement and the density resolution and spatial resolution module can be improved. Hence, this paper proposed an innovative phantom which can not only be used to evaluate image quality of dental CT, but also be suitable for the dual-energy subtraction experiment. By experimental verification, the performance of this phantom is much better than existed DIGIDENT Phantom when evaluating dental CT's image quality. A new phantom design and evaluation way were presented, which will contribute to the development of dental CT phantom.