Microstructure and mechanical properties of AM50+xTi (x=0,0.01,0.1wt%) magnesium alloys extruded from as-cast and solution treated conditions have been studied. Results show that Ti element obviously refines the microstructure of AM50 magnesium alloy and Mg17Al12 phase. Only 0.01 wt% Ti addition can make the Mg17Al12 phase turn into particles and small rod-like shape. Ti addition improves tensile strength at room temperature, and obviously improves elongation at elevated temperatures up to 200°C. The AM50+xTi alloys extruded from as-cast have better tensile strength at room temperature and better elongation at 100°C, 150°C and 200°C than that of AM50+xTi alloys extruded from solution treatment; The plasticity of AM50 magnesium alloys increases with Ti content increasing and temperature increasing for the tensile fractograph.