The study of world city has been well-established since 1995. In 1915 Patrick Geddes has first used the term world city to describe great cities in which a quite disproportionate part of the world's most important business is conducted (Hall, 1966). Friedmann, Sassen and others found that the world-wide networks of production, finance, trade, power and migration require nodal points (the world city) providing the infrastructure, information and financial resources that make the networks work (Breitung & Gunter, 2006). However, the concept of world city is not simply as the important business center or world-wide networks triggered by global economic change. This paper uses Hong Kong as a case to review the development of global city concept. The first section presents the development and the characteristic of global city. The second section we will discuss Hong Kong as a global city.