A self-made single-roll stirring (SRS) machine was used to manufacture semisolid A2017 alloy, the mechanismof A2017 alloy formation was investigated. It was shown that A2017 dendrites growing on the rough roll surface arecrashed into fragments by the roll, which move and grow freely then contribute the formation of finer spherical microstruc-ture. When casting at 710-750 ℃, fine and homogeneous spherical or elliptical grains of A2017 alloy were obtained. Ex-tending forming mould has been designed and was installed at the exit of roll-shoe gap. A2017 alloy was formed by ex-tending continuously at the semisolid state on SRS machine. Through controlling pouring temperature, semisolid formingand extending extrusion was combined organically. A2017 product with fine surface and rectangular transection of 14mmx25 mm was obtained. By contrast to the national standard, the fracture strength and elongation of A2017 products pro-duced from extending semisolid extrusion have been improved with an increase of 100 MP It was shown that A2017 dendrites growing on the rough roll surface are crashed into fragments by the roll, which move and When the at 710-750 ° C, fine and homogeneous spherical or elliptical grains of A2017 alloy were obtained. Ex-tending forming mold has been designed and was installed at the exit of roll A2017 alloy was formed by ex-tending continuously at the semisolid state on SRS machine. By controlling pouring temperature, semisolid forming and extending extrusion was combined organically. A2017 alloy with fine surface and rectangular transection of 14 mm × 25 mm was obtained. By contrast to the national standard, the fracture strength and elongation of A2017 products pro-duced from extending semisolid extrusion have been improved with a n increase of 100 MP