While Congolese judges are internationalizing their jurisprudence by asserting the direct applicability of the Rome Statute creating the International Criminal Court, the Congolese constituent expressis verbis affirms that the DR. Congo is a legal order with a monist tradition and the primacy of international law. Taking into account the cases analyzed from both a theoretical and practical point of view, the dissertation presents, following compulsory doctrine and jurisprudence, an approach that better lends credence to the dualist thesis, which thus characterizes Congolese judges in their deepest aspirations and this, relatively with regard to the choice judges make of the Rome Statute to the detriment of national temperamental laws.The book begins by analyzing the direct effect of international law in domestic law, the place of international law in the Congolese legal system and the conditions for its application by Congolese courts, as well as the constitutional basis for thedirect applicability of international treaties. This work takes a look at legal systems: monism and dualism.