國際刑法是國際法的「晚產兒」。現代意義的國際刑法，要一直到第一次世界大戰之後才誕生。所謂現代的意思，是一方面確立除了戰爭犯罪以外，違反人道與人權的行為也是國際犯罪，另一方面則是將國際刑法的權利義務主體從國家轉變到個人，「個人刑事責任原則」成了國際刑法中最重要的原則之一。然而，要真正貫徹「個人刑事責任原則」，則對個人責任的追究不能再間接仰賴國內刑事司法的協助，而必須是由一個國際司法機構直接對個人加以起訴、審判及執行刑罰，因此，國際刑法理論的完備，是與追求國際刑事法院的設立密不可分的。羅馬國際刑事法院規約正標誌著這個國際刑法史上劃時代意義的里程碑。

International criminal law is the late establishment of the international law. The modern meaning of the international criminal law was not established until the end of the World War I, It is modern in the sense that war crime is recognized as international crimes, so do crimes against humanity and human rights. On the other hand, individuals can be held responsible other than a nation, in terms of international criminal law, where individual criminal responsibility becomes one of the most important principles. Yet, solely local criminal justice is not enough to hold individuals responsible for the crime committed, therefore an international justice institution to prosecute individuals and execute penalty is needed to fully realize the principle. Inseparable, it is the establishment of international criminal theory and the founding of international criminal court. Rome Statute of International Criminal Court marks a special milestone of International criminal law history.