Abstract: The objective of this study is to test and evaluate the homogeneity of internal structure of asphalt mixtures effectively. A homogeneity identifying method based on the density of inclusions (HIMDI) of asphalt mixtures is put forward which uses X-ray CT techniques and digital image processing to consider the interaction of coarse aggregate, mastics, and air voids. Asphalt mixture specimens including four groups of asphalt-aggregate ratios are used to analyze the homogeneity of the internal structure of the specimens using the HIMDI. The results show that the homogeneity of internal structures of single or a set of asphalt mixtures specimens can be characterized through analyzing the homogeneity evaluation parameters proposed by the HIMDI, and the difference between the optimum asphalt-aggregate ratio of asphalt mixtures calculated by the HIMDI and the test result is 0.21%. This means that the HIMDI is an effective method with acceptable precision in analyzing homogeneity of internal structure of asphalt mixtures.