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A comparative study was carried out on the technological ductility during hot rolling and on the properties of rolled sheet products obtained by symmetric and asymmetric rolling of wrought, non-heat-treatable Al–Mg–Sc alloys 1545K and 1580. The study used ingots of these alloys with a cross-section of 210 × 100 mm produced on a laboratory unit. Symmetric rolling was performed to a thickness of 16 mm, after which the workpiece was cut into parts and subjected to either symmetric or asymmetric rolling with a roll-speed mismatch ratio of 1.5. Both rolling processes were carried out in the A.P. Zhilyaev Laboratory of Mechanics of Gradient Nanomaterials at Nosov Magnitogorsk State Technical University on an industrial laboratory 400 rolling mill. One of the key features of this mill is the presence of individual drives for the work rolls, which makes it possible to set different roll rotation speeds, with a maximum attainable work-roll speed ratio of V 1 /V 2 = 10/1. After hot rolling, rolled sheet semi-finished products 6 mm in thickness were obtained and examined for microstructure. Metallographic analysis showed a positive effect of asymmetric hot rolling on grain refinement in both alloys. Subsequent cold symmetric rolling was used to produce thin-sheet semi-finished products 2 mm in thickness. During cold rolling, the rolling force in the first pass was evaluated, which also demonstrated a positive effect of roll-speed mismatch. Mechanical properties were studied on the thin-sheet semifinished products in the strain-hardened condition and after annealing at 330 °C for 2 h. The resulting mechanical properties indicate that the use of asymmetric hot rolling improves the mechanical performance of alloys 1580 and 1545K. The use of speed asymmetry makes it possible to reduce the number of passes in the finishing stand for these alloys, which in turn has a favorable effect on edge quality because it prevents their premature cooling during rolling.