To obtain an inner shielding material for magnetic shielding, prepared by using an aluminum killed steel as a stock and excellent in magnetic properties, by minimizing carbon content in the course of refining at the time of steelmaking and further allowing small amounts of sol.Al. to remain at the time of deoxidation.

A steel, having a composition consisting of ≤0.005% C, ≤0.03% Si, 0.15-0.50% Mn, ≤0.01% S, 0.003-0.015% sol.Al, and the balance Fe, is continuously cast, and the resultant cast slab is hot-rolled at 1000-1200°C heating temp., 730-860°C finishing temp., and 600-700°C coiling temp., pickled, and subjected to primary cold rolling, followed by batch annealing at 650-750°C or continuous annealing at 750-900°C. Subsequently, the resultant sheet is subjected to secondary cold rolling at 6-12% draft, batch-annealed at 670-750°C, and then subjected to final cold rolling at 40-75% draft. By this method, the desired magnetic shielding material, fitted to the inside of a color picture tube and enclosing the space, through which an electron beam is allowed to pass, between an electron gun and a shadow mask or a fluorescent screen, can be obtained.