The performance of diaphragm walls in excavation for Shandao Temple Station of Taipei Metro is evaluated by using the concept of wall deflection path which is a plot of maximum wall deflections versus depth of excavation. Finite element analyses were performed and parameter studies were carried out to illustrate the sensitivity of various factors on the results. Based on the results obtained, the baseline wall deflection path is established for excavations in the T2 Zone of the Taipei Basin. It can be used in future as the basis for evaluating the influence of factors which affect wall deflections.