Abstract: The back analysis method proposed by Sakurai of Kobe University, Japan is one that can derive the complete initial state of stress and Young's modulus of the ground media in which underground openings are excavated from a set of relative displacements measured between adjacent measuring points and therefore derive the strain and the displacements of any point of the ground media or opening's lining. The calculated data are then fed back to the desigin and the construction of the openings. However, the case is right only for unlined openings but is not truelfor lined ones. In this paper three main measures to improve Sakurai's method to meet the situation of lined openings are presented.