This paper doesn’t examine the relations between China and ROK from bilateral angle as usual but from a global level. This paper points out that ROK is an important partner for China because of three reasons. The first one is that ROK will help China pursue to establish a harmonious world；the second one is that ROK can help China convince the world that china will not be a hegemon power in the future；the third one is that ROK can also act as a buffer between China and United States. Finally，this paper brings forward some suggestions to establish a strategic cooperative partnership between China and ROK.