Abstract: The mechanical behavior of cement mortar are strongly affected by its stress state and loading conditions. Compressive experiments of the cement mortar using Split Hopkinson Bar under one-dimensional, passive confined and active confined conditions were carried out, and the stress-strain curves were obtained. The affects of the stress state, loading conditions and the strain rate on the mechanical behavior of cement mortar were also discussed. Finally, a failure criterion was developed to describe the plastic behavior of cement mortar.