Magnesium alloys as the lightest structural metallic materials that human being has ever discovered can do great revolution to modern industries. However, the formability of magnesium alloys is very weak at room temperature due to the HCP structure. For wrought products, the deformation could be heterogeneous with a combination of slip and twining which provide large local variation in strain. This PhD project will use the High Resolution DIC (Digital Image Correlation) technique to study the strain distribution in both AZ31 and ZEK100 wrought magnesium alloy sheets during the complex deformation process like biaxial stretching and bending and understand the vital differences between these two materials deformed at micro-structural scale. It will also help us understand role of microstructure and texture in controlling strain localization and distribution during forming process by using complementary techniques such as SEM and EBSD in each material. Outcomes of this research will be used to infer a failure criterion and finally predict the formability of magnesium sheets by linking to crystal plasticity model.