The Large Hadron Collider (LHC) is the hadron collider with the highest colliding energy. One of its experiments, with the compact muon solenoid (CMS), aims to search for the Higgs or other new particles, to elucidate the nature of electroweak symmetry breaking, and to search for dark matter. In order to catch up with the cutting edge of high energy physics, China has decided to participate in the CMS collaboration, and has taken part in the development of the detectors such as the endcap muon detector (Cathode Strip Chamber), Resistive Plate Chamber, the magnetic yoke support structure, and so on. Now Chinese physicists are working on physics studies, where they hope to make noticeable contributions. The article gives a brief introduction to the CMS detector, its physics goals, and its importance.