Abstract: Taking the as-extruded TAZ811-1Ca alloy as object, the effect of different Ga contents (1wt%, 3wt%) on the microstructure and properties of extruded TAZ811-1Ca alloy was studied by optical microscopy (OM), scanning electron microscopy(SEM), X-ray diffraction(XRD) and tensile test at room temperature.The results indicate that the Ga addition can refine the grain of TAZ811-1Ca alloy, and the refinement effect is enhanced with the Ga content increasing. In addition, Ga element can be dissolved in α-Mg matrix resulting in solution strengthening and also promotes the dynamic precipitation of nano-sized Mg₂Sn phase during extrusion, which leads to the improvement of alloy mechanical properties.When Ga content is 3wt%, the tensile strength, yield strength and elongation of the extruded alloy reach the optimal values, which are 316.5 MPa, 210 MPa and 20.71%, respectively.