Abstract: Through the triaxial test tesults of 170 compacted soil-cement samples in laboratory,this paper further analyses the deformation properties of compacted soil-cement based on the studies on the strength properties introduced in reference 1. Reveals the relation between the strain ε_u corresponding to tne ultimate strength q_u,the ultimate deformative modulus E_u, the strain ε_0.5 corresponding to the stress of 0.5q_u and mean deformative modulus E₀. Analyses tlie effect of surrounding pressure to above telations. Proposed tke constitutional equation of stress-strain of compacted soil -cement.