It is an important problem on industrial view that metallic impurities in commercial pure aluminium Fe, Si, Cu, Mg, Mn, Zn and Cr have various influences on its properties of sheets. Up to this time many researches which was studied partially about this thema had already been reported.But there is no summarization because which contents is so wide. Among these metallic impurities, Cu, Mg, Zn and Cr are mixed from return scraps and secondary ingot, and Fe and Si are from virgin ingot.Recently with the elevation of purity in Aluminium virgin ingot, commercial composition has come into question. In Alcoa specification of impurities in 2S, sum of Fe and Si are less than 1%. In B. S. Standard Fe must be less than 0.7% and Si less than 0.5%. But practical chart of operation is reported as follows: In Alcoa, Si is 0.15%, Fe0.55% and in British Aluminium Co. Si is 0.18-0.20% and Fe more than 0.4%.From its impurities, commercial pure Aluminium must be cosidered as Al-Fe-Si ternary alloy metallurgically.In Al-Fe-Si ternary system, eutectic point of Al-Fe exists in Al-side nearer than Al-Si, and then Fe is attached greater importance to various properties than Si.In rolling pure Aluminium sheets, from metallurgical view, various properties of Aluminium sheets production are classified as follows:1) Casting crack (Hot shortness). 2) Blister and surface scratching.3) Pattern appearing on anodized aluminium sheets. 4) Corrosion.5) Mechanical properties and grain-size. 6) Orientation in deep drawing.7) Others.In this paper, we studied technically the only influence of Fe and Si in commercial pure Aluminium, that is 2S, based in light metall industry and summarized above problem.Concluson:1) Si effectively promotes its casting crack and Fe has no influence, but combination of Fe and Si have a great effect to it.2) In blister phenomenom, Aluminium purity is proportion to its appearance, but effect of Fe and Si cannot be recognized. And blister is considered to depend on gas contents of cast slab. The cause of surface fractures is not of metallic but non-metallic impurities.3) About the pattern appearing on anodized sheets, various pattern which is presumed to derive from metallic compound appearing with combination of Fe and Si.4) Corrosion property is not influenced with Fe and Si, but Al-purity.5) In these Al-purity, elongation and Erichsen value show no change with Fe and Si, but tensile strength and grain size show a great change.6) The more Fe/Si, grain size remarkably becomes the finer.