Based on the anisotropy induced by the critical stress line

the idea of transformation of stress space is presented. With reconstituted soils taken as an example

the formulas of transformation of stress space and stress increment are provided

and the influence of stress Lode’s angle is considered also. The modified Cam-Clay model is expressed again and improved in the transformed stress space; the stress-stain formulas of the improved model are presented also. Through the comparison of the computed results of four kinds of stress path by the improved model and the modified Cam-Clay model

a lot of merits of the improved model are discovered: the influence of anisotropy can be reflected better; the stress-strain characteristics of triaxial extension can be described more reasonably; the soften phenomenon of some stress path

such as

can be described.