中文摘要：

城市规模是城市经济学研究的核心问题，城市规模战略是中国城镇化战略的重要内容。相关研究主要从城市规模决定因素、集聚效应、城市规模分布规律、城市规模政策等四个方面展开。城市规模的决定因素主要包括自然条件、人文环境、经济因素以及行政级别等因素。城市的集聚效应包括经济效应、拥挤效应以及由此产生的最优城市规模问题。城市规模分布规律主要是关于规模位序法则的研究以及中国城市规模体系及其合理性的研究。城市规模理论研究为城市规模战略提供了基础，国内关于城市规模政策的争论长期存在，主要是关于大城市导向和小城镇导向的争论。

英文摘要：

The urban scale is the core issue of urban economics, and urban size strategy is an important part of China＇s urbanization strategy. This article reviews the related researches on the urban size, including the determinants of urban size, the agglomeration effects, the urban system, and the urban size policy,. It constructs a framework of the urban size theory. Determinants of urban size include the natural characteristics, the cultural environment, the economic factors and the administrative level and so on. The agglomeration effects include agglomeration economy and crowding effects, and then the optimum urban size. The researches on the urban system are mainly on the rank size law and the rationality of China＇s urban system. The urban size theory provides a theoretical basis for the urban size strategy, and the domestic debates on the urban size policy are mainly about the importance of large cities and small towns. Based on the reviews and the practical problems, the article proposes some research issues.