The microstructure and mechanical properties of micro-alloyed Mg-0.5 wt%Ce alloys are investigated systemically in this study. It shows that Mg-Ce binary system is very sensitive to extrusion temperature. On the one hand, the high tensile yield strength (TYS) of 343 MPa was obtained by extrusion at 250 °C mainly due to the combined effects of profuse nano-precipitation phase, grain refinement, texture strengthening and high-density dislocation; On the other hand, the excellent elongation of 30% was acquired by extrusion at 300 °C resulting from the elimination of dislocations as well as the modification of texture.