Abstract: City portrait is an essential technology and precondition for realizing refined governance of cities. This study intends to explore the functional mechanism and implementation patterns of city portrait in the governance of modern cities.[Design/Methodology］By combing the three key elements which are massive urban data, scientific and effective urban computing model and visual human computer interaction system, this research analyzes the current application status and developing trends of city portrait in refined urban governance from the perspectives of systematicness, variety and complexity.
［Findings/Conclusion］An application system of city portrait has been developed from three dimensions which are resource, field and application. Meanwhile, the application process of city portrait used in refined city governance has been revealed. It is a reform process characterized by data as the core, integrating and coordinating resources of various functional facets and industrial sectors in cities, prospective prediction, scientific decision making, precisely refined governance and targeting at the city in the future. ［Originality/Value］This paper successfully establishes logic associations between city portrait and governance provides a clear thinking for building city portrait, and also broadens the research area of urban governance.

Key words: Refined city governance, City portrait, Constitutive elements, Application system