中文摘要：

城市群是指以中心城市为核心向周围辐射构成的多个城市的集合体。城市群的形成是经济发展和产业布局的客观反映,并已成为发达国家城市化的主体形态。进入21世纪,中国加入世界贸易组织,沿海城市群成为国家外向性经济、出口贸易和＂世界工厂＂的主要地区,以城市群为主体推进中国城市化进程成为中国特色城市化道路的重要选择。本文重点就城市群概念、城市群国外研究、中国城市群的早期研究、中国城市群作为国家战略的研究进行了综述,对中国城市群研究进行了展望。本文认为：中国城市群形成机制较西方发达国家和地区要复杂得多,相关研究也需要结合中国国情进行理论和方法的创新。

英文摘要：

Urban agglomeration is a complex with the central city as the core surrounded by two or more cities.It is the objective reflection of the economic growth and social development as well as industrial layout in a region.It has also become a main form of urbanization in developed countries.In fact,the ＂urban agglomeration＂ concept in China is the characteristics of a noun,no equivalence in foreign countries.In Western literature,the ＂urban agglomeration＂ means ＂urban cluster＂,that is,a big city and its surrounding satellite towns in remote sensing image formed the connected irregularities each other,and the spatial range includes ＂urbanization area（UA）＂ and ＂metropolitan area（MA）＂.Sometimes,some of metropolises connected each other are also called as urban agglomeration.United Nations gave a definition of urban agglomeration as follows： ＂Comprises a city or town proper and also the suburban fringe or thickly settled territory lying outside,but adjacent to,its boundaries.A single large urban agglomeration may comprise several cities or towns and their suburban fringes.＂ Therefore,urban agglomeration in the Western concept includes the cities,towns and urban-region outlying areas.＂Urban agglomeration＂ in China refers to geographical concepts of a group of major cities which are similar and interactions among administrative,transportation,economic,and social fields.In the 21st century,thanks to China＇s entry into the World Trade Organization,a national coastal urban agglomeration has become the main region for the national trade economy,export and the ＂world manufacturing bases＂.Urban agglomeration as an important urban spatial pattern was a unique choice to promote the process of urbanization in China.This article reviewed some progress in studies of urban agglomeration,such as the concept of urban agglomeration,overseas research of urban agglomeration,early researches of Chinese urban agglomeration and studies on Chinese urban agglomeration as a national strategy.This paper