国际法上的强行法是指全体国际社会成员所公认且在缔约时不能贬损的国际法律规范。国际强行法的渊源有条约、习惯,以及其他渊源。识别强行法,既要看其目的,又要看其法律效力如何。强行法的范围已经达成一定的共识,但仍处在发展中。实践中,我们既要看到强行法的积极作用,又要重视它的消极影响。 Forced law in international law refers to the international legal norms that are universally recognized by all members of the international community and can not be derogated from when contracting. Sources of international jus cogens are treaties, customs, and other origins. Identify jus cogens, both to see its purpose, but also depends on its legal effect. The scope of jus cogens has reached some consensus but it is still under development. In practice, we should not only see the positive role of jus cogens but also attach great importance to its negative impact.