The paper argues that the competence-competence principle has become a structural cornerstone of commercial arbitration, yet its operation remains uneven across legal systems and between its positive and negative effects. It first traces the historical and doctrinal genealogy of competence-competence and its close relationship with separability, showing how continental European theory, the UNCITRAL Model Law, case law in the US and UK, and leading scholarship together construct a conceptual framework that empowers arbitral tribunals to rule on their own jurisdiction while postponing full judicial control. It then analyzes how this framework is embodied in key international instruments and in the legislation and practice of France, Germany, the United States and China, highlighting particularly the divergent strength of the “rule of priority” or negative effect in channeling courts toward prima facie rather than full review at the gateway stage. Using a doctrinal and empirically informed comparative method, the study shows that China’s current regime still gives courts and institutions a structurally privileged role in jurisdictional questions, which weakens both the positive and negative effects of competence-competence despite formal recognition in statutes and arbitral rules.  We suggest that a calibrated strengthening of the negative effect through a clearer priority rule in favor of arbitral tribunals, combined with targeted, post-award judicial review, as a way to better reconcile party autonomy, procedural efficiency and judicial legitimacy in Chinese and international commercial arbitration.