近年來國際法規範多元擴展與爭端裁決機構大幅增加使國際法律秩序可能面臨「破裂化」(fragmentation)成為普遍的關切。隨著區域貿易協定(regional trade agreements, RTA)及其爭端解決機制之大幅增加，管轄權衝突或裁判衝突之風險似亦存在於國際貿易法秩序之中。一方面，針對WTO-RTA法規競合的貿易爭端，WTO與RTA均具有管轄權，可能產生管轄權衝突。另一方面，由於WTO未規定WTO-RTA爭端解決機制之互動關係，爭端裁決機構在平行的爭端解決程序下審理同一或類似義務，亦可能產生裁判衝突。從WTO爭端實務Mexico-Soft Drinks、Argentina-Poultry、Brazil-Tyre等案件觀察，WTO爭端解決機制對RTA法律秩序之維持並未展現一致的司法調和。 本文認為，全球貿易秩序運作的可預測性與法律安定性有賴於WTO與RTA爭端解決機制間維持和諧之關係。未來小組或上訴機構能否或如何透過法律障礙概念、國際法原則與條約解釋或其他有助於融合的規範工具，務實回應減緩WTO-RTA司法衝突之需求，值得觀察。惟長遠觀之，WTO-RTA之融合，或應由會員於WTO架構下，透過談判之過程，從體制面設計若干基本原則以管理WTO-RTA爭端裁決機構之互動關係，並由兩貿易體系所共通適用。

The expansion of the coverage of international law and the increasing number of international tribunals have led to the issue of ”fragmentation” of international legal order becoming widespread concern in recent years. Given the proliferation of regional trade agreements (hereinafter RTA) as well as its dispute settlements, the risk ensuing from the conflicts of jurisprudences and rulings seems also to exist within international trade law. On the overlapping subject matter, the WTO and RTA share common jurisdiction. In addition, the lack of clear rule in regard to the interaction between WTO and RTA tribunals may also contribute to the occurrence of conflicting rulings given that each tribunal may adjudicate parallel or similar obligation in parallel dispute settlement procedures. In light of the cases of Mexico-Soft Drinks, Argentina-Poultry and Brazil-Tyre analyzed in this paper, we may find that the WTO adjudicators do not show judicial coherence towards the preservation of RTA legal order. In this paper, the author argues that the operation of the global trade order as well as its predictability and legal certainty depend on how WTO and RTA trading systems may create judicial accommodation and fit each other. In this sense, whether or how the future panel or the Appellate Body can pragmatically respond to the need of alleviating the WTO-RTA judicial conflicts through certain normative instruments found in the past practices, such as the concept of ”legal impediments”, the principles of international law or the tool of treaty interpretation is worth further observing. In the long term, it is suggested that WTO Members should devise a set of principles to manage the interaction between WTO and RTA tribunals, which is concurrently shared by both trading systems.