Asymmetric excavation has become increasingly common with the development of construction and the progressive collapse caused by the local component failure has attracted many attentions. Aiming at this problem, the three-dimensional finite element software PLAXIS 3D is adopted to analyze the response of the whole retaining system to the asymmetric excavation after local component failure through the method of removing component. The results show that when the braces fail, the earth pressure of piles decreases in the failed area because of the unloading effect but is opposite in the adjacent area. Meanwhile, the moments of piles near intact braces increase greatly. The earth pressure and moment of piles on the same side of the failed piles increase greatly, while on the opposite side they decrease as piles get failed. Piles on the deep side push piles on the shallow side through braces, but the displacement reverses when piles on the deep side failed. The value of soil settlement on the shallow side is less than that on the deep side and increases with the increasing number of failed piles, but the range of settlement almost keeps unchanged. Earth pressure variation coefficient and moment transfer coefficient get surge when the depth difference increases. In addition, the change of depth boundary line has little effect on the earth pressure and pile moment. Finally, a design method is proposed to improve the redundancy of supporting structure through enlarging the reinforcement moment of piles.