The microstructure and mechanical properties of as-cast and as-extruded Mg-Zn-Y alloy (Mg-11%Zn0.9%Y, mass fraction) containing Mg3 YZn6 quasicrystal were studied. The eutectic icosahedral quasicrystal phase (I-phase) is broken and almost distributes along the extrusion direction, and fine I-phase with nano-size is precipitated during the extrusion. The α-Mg matrix grains are refined due to recrystallization occuring during the hot extrusion. Some {10-12} twins are observed in the extruded ZW1101 alloy. And {0002} fiber texture is formed in matrix alloys after hot extrusion. The extruded alloy exhibits high strength in combination with large elongation at room temperature. The strengthening mechanism of the as-extruded alloy was discussed.