A method of manufacturing an Fe-based metal plate comprising: forming a metal layer containing a ferrite former on at least one surface of a base metal plate of an α-γ transforming Fe or Fe alloy; next heating the base metal plate and the metal layer to an A3 point of the Fe or the Fe alloy so as to diffuse the ferrite former into the base metal plate and form an alloy region of a ferrite phase in which an accumulation degree of planes parallel to a surface of the Fe-based metal plate is 25% or more, and an accumulation degree of planes parallel to a surface of the Fe-based metal plate is 40% or less; and next heating the base metal plate to a temperature equal to or higher than the A3 point of the Fe or the Fe alloy so as to increase the accumulation degree of the planes to 30% or more and decrease the accumulation degree of the planes to 30% or less while maintaining the alloy region of the ferrite phase to obtain the Fe-based metal plate comprising 1% or more of a ferrite single phase region in terms of an area ratio in a thicknesswise cross section of the Fe-based metal plate, wherein the base metal plate has the A3 point within a range of about 600°C to 1000°C, the ferrite former is at least one kind selected from a group consisting of Al, Cr, Ga, Ge, Mo, Sb, Sn, Ti, V, W, and Zn, and as the base metal plate, used is one in which such a working strain is brought about by cold rolling that dislocation density is not less than 1 × 10 15 m/m 3 and not more than 1 × 10 17 m/m 3, one in which a working strain is brought about by cold rolling in which rolling reduction ratio is not less than 97% and not more than 99.99%, one in which a working strain is brought about by shot blasting, one in which a working strain is brought about by cold rolling in which rolling reduction ratio is not less than 50% and not more than 99.99% and shot blasting, one in which a shear strain of 0.2 or more is brought about by cold rolling, or one in which a shear strain of 0.1 or more is brought about by cold rolling and a working strain is brought about by shot blasting, and wherein the accumulation degree of planes and the accumulation degree of planes are measured by X-ray diffraction using a MoKα ray. forming a metal layer containing a ferrite former on at least one surface of a base metal plate of an α-γ transforming Fe or Fe alloy; next heating the base metal plate and the metal layer to an A3 point of the Fe or the Fe alloy so as to diffuse the ferrite former into the base metal plate and form an alloy region of a ferrite phase in which an accumulation degree of planes parallel to a surface of the Fe-based metal plate is 25% or more, and an accumulation degree of planes parallel to a surface of the Fe-based metal plate is 40% or less; and next heating the base metal plate to a temperature equal to or higher than the A3 point of the Fe or the Fe alloy so as to increase the accumulation degree of the planes to 30% or more and decrease the accumulation degree of the planes to 30% or less while maintaining the alloy region of the ferrite phase to obtain the Fe-based metal plate comprising 1% or more of a ferrite single phase region in terms of an area ratio in a thicknesswise cross section of the Fe-based metal plate, wherein the base metal plate has the A3 point within a range of about 600°C to 1000°C, the ferrite former is at least one kind selected from a group consisting of Al, Cr, Ga, Ge, Mo, Sb, Sn, Ti, V, W, and Zn, and as the base metal plate, used is one in which such a working strain is brought about by cold rolling that dislocation density is not less than 1 × 10 15 m/m 3 and not more than 1 × 10 17 m/m 3, one in which a working strain is brought about by cold rolling in which rolling reduction ratio is not less than 97% and not more than 99.99%, one in which a working strain is brought about by shot blasting, one in which a working strain is brought about by cold rolling in which rolling reduction ratio is not less than 50% and not more than 99.99% and shot blasting, one in which a shear strain of 0.2 or more is brought about by cold rolling, or one in which a shear strain of 0.1 or more is brought about by cold rolling and a working strain is brought about by shot blasting, and one in which such a working strain is brought about by cold rolling that dislocation density is not less than 1 × 10 15 m/m 3 and not more than 1 × 10 17 m/m 3, one in which a working strain is brought about by cold rolling in which rolling reduction ratio is not less than 97% and not more than 99.99%, one in which a working strain is brought about by shot blasting, one in which a working strain is brought about by cold rolling in which rolling reduction ratio is not less than 50% and not more than 99.99% and shot blasting, one in which a shear strain of 0.2 or more is brought about by cold rolling, or one in which a shear strain of 0.1 or more is brought about by cold rolling and a working strain is brought about by shot blasting, and wherein the accumulation degree of planes and the accumulation degree of planes are measured by X-ray diffraction using a MoKα ray.