Abstract: In this paper, the structural problems of a box-type subway tunnel and their impact on structure safety is analyzed considering such features as large integral rigidity, vulnerability against deformation, and likelihood of being affected by surrounding construction activity. The index and control values of safety monitoring for this type of structure are presented in accordance with a statistical analysis of cross section, space deformation, and internal force features of a box-type tunnel under the influence of surrounding construction activity. The results of this analysis and its application show that the proposed method for defining the index and control values for safety monitoring is safe and reliable and can provide a reference for structural safety monitoring in similar works.