This thesis examines the constitutional significance of WTO memberships of China, Taiwan, Hong Kong, China and Macau, China and their contribution to judicial settlement of trade disputes. I firstly present the complexities of legal bases and accession histories of these four members, point to the need for a strengthened judicial protection in external trade areas, and then explain why a constitutional approach toward WTO law will contribute to judicial settlement of trade disputes and thus enhance peace and security among them. In this context, I analyze existent provisions pertaining to domestic judicial review under the WTO Agreement. I also examine the obligation to provide an independent and impartial judicial review as embodied in China's Accession Protocol by reference to global and regional standards on judicial independence and impartiality. I also explore its implication to Chinese judicial reform. In respect of Taiwan, I examine existent constitutional/legal regulatory regime on China trade policy and relevant jurisprudence. I also use a case study to illustrate how a constitutional approach to WTO law and an approach based on domestic administrative law lead to different answers. I then continue to examine existent trade settlement mechanisms at different levels. I start with trade disputes between China and Taiwan. I argue that third party participation offers a good alternative for them to interact with each other in the WTO Dispute Settlement Mechanism. Domestic judicial protection is insufficient and ineffective and needs strengthening. Given the direct transportation agreements signed in 2008, I also slightly touch upon the 'prompt negotiation' clause therein. In the case of China and Hong Kong, China and Macau, China, I conclude that there is a danger for the erosion of autonomy of these two special administrative regions from interference of the Central Authority through legislative interpretation. I also argue that these three members tend not to go for the WTO forum. In addition, the Closer Economic Partnership Arrangements should include a dispute settlement mechanism with higher degree of judicialization. Regarding Taiwan and Hong Kong, China and Macau, China, I argue that 'China factors' are of decisive importance. I then explain why the WTO forum is not preferable to these three members and why the private international law approach seems more appealing. All through this thesis, I emphasize on the importance of preserving and ensuring peace and security. A constitutional reading of their WTO memberships will help these four members to constitutionalize their external trade policy-making where judicial governance, particularly the WTO Dispute Settlement Mechanism, is underlined. Only through judicial settlement of trade disputes among these four members can the cross-strait perpetual peace be sustained.