This paper takes HeFei Metro Line1, Line2 subway transfer station deep excavation engineering as the background, using FLAC^3D to establish the model, simulating the process of excavation, what's more,the supporting systems of deep foundation pit are analyzed, considering the interaction between supporting structure and soil, calculating and analysing of the diaphragm wall internal forces and deformation, and by comparing the calculation results of various working conditions, the distribution law of the unsymmetrically loading and irregular diaphragm wall of internal force and deformation were obtained. The calculation and analysis results showed that the main stress of deep foundation pit supporting structure of irregular is bigger than the straight arm's, and the stress concentration phenomenon is more obvious, the horizontal deformation is larger than the arm's under the same conditions, the force and deformation for unsymmetrically loading and irregular is worst case in deep pit. The results of the study which is for future subway station deep foundation pit engineering design, construction provide the basis necessary reference.