Abstract: The objective of digitizing shield tunnels is to visualize the complicated underground world,manage the whole life-cycle data of engineering projects dynamically,and facilitate engineering analysis and decision-support,so as to lead to a more efficient use of engineering information.A shield tunnel digital platform which is constructed by adopting client-server architecture is proposed at first.Then based on the idea of decomposing the geometrical objects of shield tunnels,data taxonomy and data model of digitized shield tunnel are presented.Geometrical modeling of shield tunnels and surrounding ground is discussed.A visualization and dynamic information management scheme for the digital platform is also put forward.Finally,an engineering application study of Shanghai Yangtze River tunnel project is provided.