Abstract: With the rapid development of Internet, people can get increasing number of valuable data from various platforms. Effective visual analysis of data from professional websites like Autohome can be used to grasp the competitive community and disadvantages of products. In this paper, we proposed an algorithm MDect based on graph mining to detect the competitive market of specific cars. Experiments demonstrate that our method achieves a good balance between structural and attribute similarities. An interactive system containing chord diagram, stream and cloud tags were developed to display the competition. Eventually we illustrated the utility of visualization through user study and cases.