Abstract: The present disclosure provides a method for automatically identifying a ring joint of a shield tunnel based on a lining structure. The method includes the following steps: S1: acquiring a three-dimensional (3D) point cloud of a shield tunnel through a mobile scanning system: S2: generating an orthographic projection image of an inner wall of the tunnel: S3: identifving a feature of a bolt hole; S4: extracting a longitudinal joint of the shield tunnel: S5: generating a prior structural template ring; and S6: extracting a transverse joint of the shield tunnel. The present disclosure has the following advantages. Starting from the features of the lining structure of the shield tunnel, the present disclosure selects a bolt hole with a strong structural feature, takes the structural feature of the bolt hole as an identification feature, and indirectly extracts joint information of straight and staggered joints tunnel.