Soil improvement is one of the most important problems to be solved for shielding tunneling in the complex strata. Now the foam modifying soils technique has been widely used in shield tunneling construction. A new foaming agent used for soil properties improvement is developed and presented in this paper. This paper presents test research of soil properties improvement on sand in rich-water strata and clay soils from permeability, fluidity, compressibility and shear strength. Compared with the imported and domestic foaming agent, the basic performances of the newly developed foaming agent are obtained. Some conclusions are drawn in the paper, and it is significant to improve the engineering properties of soil and reduce the ground damage in shield tunneling construction.