英國於2016 年6 月23 日舉行脫歐公投，脫歐陣營以51.9% 得票率勝出，震驚世界。英國於1973 年1 月1 日加入歐盟，因為無法分享法國與德國在歐盟的領導權，且一向抗拒移轉更多主權給歐盟，反對歐盟朝向政治同盟方向發展，英國內部因此一直存有強烈疑歐聲音以及脫歐要求。脫歐公投已引發英鎊重跌，衍生更多問題及不確定性。英國於2017 年3 月29 日正式啟動《歐洲聯盟條約》第50 條的脫歐程序。英國與歐盟未來貿易關係，何去何從，是合作或對抗，在攸關英國與歐盟的興衰以及西方團結。英國脫歐乃是一件重大國際事件，具有深遠的影響。本文將從法律方法與國際政治經濟學觀點，研究英國脫歐有哪些原因及爭議？帶來哪些影響？英國與歐盟如何進行脫歐談判？又有哪些模式用以架構雙方新的貿易關係？本文建議WTO-plus FTA 得做為英歐未來貿易合作關係之一項最佳模式。 The UK has been a member of the European Union (EU) since 1973. However, a national referendum, held on 23 June 2016, resulted in a 51.9% vote to exit the EU. The Brexit referendum has brought a strong shock and impacts on both the UK and the EU, and it also poses a high uncertainty for the UK-EU trade relationship in the future. The Brexit has emerged as an important issue that needed to have a deep study. Accordingly, this paper will examine the following core issues: What are the causes of Brexit? How to trigger Article 50 procedure? What are the impacts of Brexit on the pound sterling, British economy, immigration, etc.? What are the models for the future trade UK-EU relations? What lessons for the EU and its future reforms? In general, the Brexit marks a backward step of European integration, and will be undertaken with a series difficult negotiations and adjustments by both UK and the EU in the coming years. It is expected that the UK and the EU will develop a new cooperative model for their future trade relationship. This paper proposes the WTO-plus FTA as one of the best options for the future UK-EU trade cooperation relations.