Low rare-earth containing magnesium (Mg) alloys are considered lightweight structure materials and are wildly used in automotive and aerospace industry. Tensile and fatigue behaviors are two important mechanical properties of metallic alloys. This research focused on the tensile and fatigue properties of ZEK100 Mg alloys. Microstructure of ZEK100 alloy contained equiaxed grains and exhibited relatively weaker texture compared with other RE-free Mg alloys. During tensile test, as the strain rate increased, yield stress, ultimate tensile strength and hardening capacity increased, but the elongation decreased. Strain rate was found to influence tensile properties of ZEK100 Mg alloy. The stress controlled fatigue test showed that as the stress ratio increased, the stress amplitude and the fatigue life both decreased. Fatigue crack was observed to initiate from specimen surface, and crack propagation was characterized by fatigue striations.