The nano-quasicrystal reinforced Mg-Zn-Y alloy has ultra-high elongation at room temperature and has broad application prospects. It is necessary to further study its hot deformation behavior to provide a theoretical and application basis for subsequent processing. In this research, Mg-1.92Zn-0.34Y (wt%) alloy containing nano-quasicrystalline particles was prepared by semi-solid and hot extrusion composite process. The high temperature deformation mechanism of the alloy at temperatures of 250, 300 and 350 ℃ and strain rates of 10^-3, 10^-2 and 10^-1 s^-1 was investigated. The effect of nano-quasicrystal particles on hot deformation behavior of Mg-1.92Zn-0.34Y alloy was studied. The results show that the high-ductility Mg-1.92Zn-0.34Y alloy with nano-quasicrystals can be prepared by the combination process of semi-solid and hot extrusion. The processed alloy exhibits a high tensile elongation to failure (EL) of 44%±2.6%, ultimate tensile strength (UTS) of 258±2.0 MPa and yield strength (YS) of 176±1.6 MPa at room temperature. The average deformation activation energy and stress index of Mg-1.92Zn-0.34Y alloy according to the constitutive equation are 271.7812 kJ/mol and 6.7838, respectively. The alloy has good thermoplasticity and no instability phenomenon occurs under experimental conditions, which indicates that the presence of nano-quasicrystals improves the deformation ability of the alloy. The optimal hot working region is 330–350 ℃ and 10^-3–10^-2 s^-1, that is, the high-temperature and low strain rate region.