Abstract: Basted on the monitoring data of a deep foundation pit adopted the "T" Diaphragm wall, this paper illustrates the temperature effect on steel bar gauge measurement. of the "T" Diaphragm wall, and provides amendment coefficients of temperature effect. Through analysis the law of the "T" Diaphragm wall stress in different sections and the corresponding values of moment and axial force, some conclusions and recommendations are given for the similar engineering projects.