To solve the problem of mismatch between design parameters and actual mechanical properties of pavement structure， typical cement stabilized macadam was selected to carry out uniaxial compression and direct tensile tests under different cement dosages and loading speeds. The stress-strain characteristics were studied， and the variation of compressive and tensile strength（Rc & Rt）/ modulus（Ec & Et）/ Poisson’s ratio（μc & μt） and their relationships were analyzed， revealing the different mechanical properties of cement stabilized macadam under tension and compression. The results show that the stress-strain properties of cement stabilized macadam under tension and compression are in accordance with the bilinear characteristics of bi-modulus theory. A cement dosage range of 2% to 3% is identified as the transition zone where the mechanical properties change. The tensile and compressive parameters exhibit a strong nonlinear relationship with the loading speeds and cement dosages. Among the influencing factors， the influence of cement dosage on tensile and compressive parameters is much greater than the loading speed. In terms of mechanical parameters， the modulus is most affected by cement dosage and loading speed， followed by strength， and Poisson’s ratio. Compared with compressive parameters， tensile parameters are more significantly affected by these two factors. The Ec/Et and the μc/μt are less affected by loading speed and cement dosage. The Rc/Rt decreases gradually with the increase of cement dosage. When the cement dosage exceeds 3%， the Rc/Rt tends to be stable. Based on these findings， a quantitative value model for the tensile and compressive mechanical parameters of cement stabilized macadam is established. The research results can provide a basis for the parameter value of pavement structure design based on bi-modulus theory.