Through three years of the Korean War and the strengthenrole of the Cold War system, China and North Korea determinedto build a relation of allicance in the form of mutual asistance inthe early 1960s. During the Cold War, Sino-Korean alliance hadits characteristics of the era and it brought a security guaranteeand practical interests to maintain the geopolitical and military balance in Northeast Asia. Since the end of the Cold War,China-DPRK realations have not been so stable because of theinfluence of international political situation changes. With theescalation of the nuclear issue and the development ofChina-ROK relations in recent years, Sino-DPRK allicance basiswhich was “sealed in blood friendship” has been questioned. Is itto continue to consolidate the alliance and to develop theall-round cooperation partnership, or to repeal the treaty ofalliance and return to a normal state relations? The decisivefactor still lies on the national security and practical interests.Under the influence of the current international situations, thehistorical ambiguity will continue to maintain in the alliancebetween China and DPRK.