One of the main reasons leading to foundation pit failure is that the design method is not suitable. In order to solve the problem, a methodology for foundation-pit modeling is described. Based on the methodology, both limit equilibrium analysis and numerical modeling one are compared. Their advantages and limitation are proposed. Finally, an actual foundation-pit project is modeled. The simulating results of two kinds of methods are compared. The results show that numerical modelling method can better reveal the laws of stress and deformation for foundation-pit than limit equilibrium one.