Abstract: A new 3D design and analysis method was put forward,including its theory,formulas and corresponding FEM software.Moreover,the 3D method and software was applied to the actual deep foundation pits in the city of Ningbo and the contrast analysis between the calculated data and measured data was presented.It was shown that the new design method was a kind of new solution for complicated deep foundation pits,and the ratio of the calculated data to the measured data was mostly in the range from 0.6 to 1.5.Therefore,the present method and software could be applied to actual design of foundation pits with safety and satisfactory economic benefit.Furthermore,it could be considered as the supplement or improvement to the active technical specification(JGJ120—99) to some extent.