The present work aims at to study the evolution of crystallographic texture and its contribution to the mechanical behavior of Mg at room temperature. The samples were made from the as-received large pieces of Mg with variation of angles with respect to the rolling direction (RD). ASTM standard tensile specimens were cut at 0 o (RD), 45 o , and 90 o (TD) from the RD. The influence of the dislocation microstructure and the crystallographic texture developed during the plastic deformation on the mechanical behavior of the material during tensile test was analyzed by transmission electron microscopy, x-ray diffraction and numerical simulationsusing the polycrystalline viscoplastic self-consistent model. The results showed that the AZ31 alloy presented a strong mechanical anisotropic behavior during loading, characterized by a decrease of the flow stress with the increase of angle between the two deformation paths. According to the calculations, this behavior is associated with a decrease of the average Taylor factor due to the development of a (0001) <100> type crystallographic texture during tensile test.