The industrial CT was used for getting the crosssection images of asphalt mixture. Based on digital image processing methods, the coarse aggregates were extracted from the images, and the adhesion problem of coarse aggregates particles was resolved successfully. The judgment criterion of contact between particles was established, and a 5 pixel×5 pixel size window was designed for contact searching along the particle boundary. After total 640 images were searched by these procedures, the data were analyzed qualitatively, and a contact degree indicator(C) was tried to establish. Four different probability density distribution functions were used to fit C data, and the validity of fit was tested by KolmogorovSmirnov and Chisquare methods. Finally, the lognormal distribution was determined for describing the contact characteristics of coarse aggregates particles.