Abstract: A novel extrusion approach, entitled slope extrusion (SE), was employed to manufacture AZ31 (Mg–3Al–1Zn, wt%) alloy sheets. The microstructures, textures, and mechanical properties were investigated, compared with those of the AZ31 sheet fabricated by conventional extrusion (CE). Through the combination of finite element simulation and actual experiment, the ultimate results indicated that significant grain refinement (from 9.1 to 7.7 and 5.6 μm) and strong basal texture (from 12.6 to 17.6 and 19.5 mrd) were achieved by the SE process. The essence was associated with the additional introduced inclined interface in the process of SE, which could bring about more asymmetric deformation and stronger accumulated strain along the ND when compared with the process of CE. As a consequence, the SE sheets exhibited a higher yield strength (YS) and ultimate tensile strength (UTS) than the counterparts of the CE sheet, which was mainly assigned to the synergistic effects from grain refining and texture strengthening.