虛擬世界是一種三度空間的環境模擬，其內容由操作者、使用者或雙方共同產生。現今規模最大且最著名的虛擬世界是由林登研究公司或林登實驗室所開發的第二人生。第二人生的線上虛擬世界經濟效益受到現實玩家與公司、大企業等重視，不僅許多知名汽車、運動用品、飲料等商品紛紛進駐開設門市，許多知名的公司企業也紛紛參與加入第二人生，例如：愛迪達、可口可樂、迪奧等。保護虛擬世界中的商標，其中一個主要的癥結點在於「虛擬商標是否被轉換成實際的真實利益使用」，另有關虛擬商標是否屬「合理使用」、虛擬世界中的「商標侵權」問題、商標的保護等，上述爭議皆為本文所欲探討之範疇。

This study introduces the relevant issues on trademark in the virtual world. The virtual world is a three-dimensional environment simulation, coproduced by operators, users, or both. Second Life developed by Linden, Research Inc. (or Linden Lab)is the largest and the most famous virtual world in the present day. The relevant players, well-known companies, and large enterprises have been paid much attention to the economic benefits of online Second Life in virtual world and have involved in adding into second life stores, such as Adidas, Coca-Cola and Dior etc. One of the main topics on protection of trademarks in the virtual world is weather the virtual trademark is converted into the actual real interest. Others are fair use of trademark, trademark infringement, trademark protection in virtual world, and etc. These critical issues are also what author wants to explore in the article.