Abstract: Composite soil nailed wall is a newly support technology that is different from the traditional soil nailed.This paper,by using the FEM,researches the axis force of the composite soil nailed wall in different excavating phases and different loess soil areas that are full of underground water and bearing mechanic composite layer.We can draw the conclusion that axis force of the composite soil nailed wall is different in different condition and different excavating phases,which gave a benefit reference on more research.