The hot compression deformation behavior of the Mg-6Zn-1Mn-0.5Ca(ZM61-0.5Ca) and Mg-6Zn-1Mn-2Sn-0.5Ca(ZMT612-0.5Ca) alloys have been investigated in this study under the temperature range from 250~400 °C and the strain rate range of 0.001~1 s-1. The results show that the DRX was promoted with addition of Sn, and CaMgSn can act as nucleation sites during compression deformation. Flow stress increased with increasing strain rate and decreasing temperature. The ZM61-0.5Ca and ZMT612-0.5Ca alloys had obvious dynamic recrystallization characteristics. CaMgSn phases can effectively inhibit dislocation motion with addition of Sn, thus increasing the peak ?ow stress of the alloy. The addition of Sn increased the hot deformation activation energy of the ZM61-0.5Ca alloy from 199.654 kJ/mol to 276.649 kJ/mol, thus improving the thermal stability of the alloy. The optimal hot deformation parameters of ZMT612-0.5Ca alloy were the deformation temperature of 350~400 °C and the strain rate of 0.001~ 0.01s-1.