Abstract: The deformation behaviors of AM60B magnesium alloy at different strain rates were investigated by way of compressing columniform cast ingots at 573 K.It was found that the flow stress raises along with the strain rate increasing as well as the compression ratio decreases.The compressive deformation constitutive equation of AM60B Mg alloy at different strain rates was established by means of mathematical statistics.And the experiments indicate that the constitutive equation can describe the compressive deformation rules of AM60B Mg alloy at different strain rates precisely.