Magnesium alloys and very light metals that can be used for structural application. A variety of Mg-Li-Zn alloys including Mg-11%Li-1%Zn, Mg-9%Li-1%Zn, Mg-9%Li-1%Zn-0.2%Mn, Mg-9%Li-1%Zn-1%Al-0.2%Mn and Mg-9%Li-3%Al-1%Zn-0.2%Mn were processed by equal channel angular extrusion (ECAE) to see how effective is this process in refining the grain structure. After 4 passes of the ECAE process, TEM studied the microstructural diversifications, especially showing the existence of compounds, MgLiZn, MgZn2 and ZnO. The room temperature and high temperature mechanical properties were also investigated. After the ECAE process, the room temperature strength was found enhanced at a modest cost of reduction in elongation.