中文摘要：

在我国高速发展的城镇化背景下,城市群成为推动我国社会经济发展的重要引擎。选定长三角、珠三角、京津冀、长中游和成渝五个城市群为研究对象,通过分析城市群中的城市中心性指数发现城市群中各城市在职能上呈现等级分布;每个城市群都拥有核心城市作为支柱带动城市群发展,核心城市具有显著的服务业中心性指数,制造业中心性突出的城市是推动城市群发展的基础。长三角和珠三角正处于城市群发展完善阶段,拥有多个核心城市联动发展;京津冀和成渝处于城市群的发展不均衡阶段,核心城市与其他城市分化明显;长中游仍处于城市群初级阶段,城市的中心性指数低,城市间联系强度低。

英文摘要：

Under the rapid urbanization in China,mega-region becomes an important engine to promote the social-economic development. This paper employs 5 main mega-regions（ Yangtze River Delta; Pearl River Delta; Jing-Jin-Ji; Cheng-Yu; Middle Reaches of the Yangtze River） to conduct the urban centrality of mega-regions. Based on the analysis of urban centrality of megaregions,this paper explores cities in the mega-regions has urban function hierarchy. Each mega-region produces core cities,and the service industry makes up a high percentage of centrality index in core cities. The cities with high manufacturing centrality are the cornerstone for mega-region development. Yangtze River Delta and Pearl River Delta are in the improvement stage,which have multiple core cities to enhance the development of mega-regions. Jing-Jin-Ji and Cheng-Yu are in the imbalanced development stage,which producesa significant gap between core citiesand other cities; Middle Reaches of the Yangtze River is in the infancy stage with low the urban centrality,which has low activities degree between each city.