<p>Extrusion machining with arrayed sawteeth (EM-AS) is a new method for severe plastic deformation (SPD). Under the combined action of saw-tooth structure extrusion and tool cutting extrusion, EM-AS can be used to fabricate metal sheets with double-sided gradient structures at room temperature. In this paper, the deformation process, process mechanism, microstructure, and mechanical properties of pure aluminum sheet with double-sided gradient structure under different saw-tooth heights are studied. The results show that the forming process can be divided into four stages i.e., through the saw-tooth channel, the forming of the sheet metal tip, the initial forming of the sheet metal, and the stable forming of the sheet metal, and the processed sheet has obvious double-sided gradient structures in strain, grain size, and hardness. When the saw-tooth height increases from 0.15 to 0.45 mm, the lateral extrusion ratio of pure aluminum sheets prepared by the EM-AS process decreased significantly, and the surface roughness increased from 71.05 to 96.48 μm, the hindrance of the extrusion channel increases, which is unfavorable to the material extrusion from the lateral channel. In the meantime, the maximum strain of the deformed layer also increases significantly, which made the yield strength (YS) increased from 109 to 138 MPa and the ultimate tensile strength (UTS) increased from 124 to 169 MPa, and the elongation at break (λ) decreased from 25.2 to 22.4%. Therefore, the distribution of the gradient structure in the thickness direction can be controlled by controlling the saw-tooth height.</p>