Abstract: A fine amorphous metal wire with a circular cross section that has improved toughness and a composition represented by the formula:Fe.sub.a Co.sub.b Cr.sub.c Si.sub.x Bywhereina+b is from about 53 to 80 atomic %;c is from about 3 to 20 atomic %;x is from about 5 to 15 atomic %; andy is from about 5 to 15 atomic %;provided that ##EQU1## is in a range from about c.times.0.025+0.25 to c.times.0.012+0.73; and x+y is from about 17 to 27 atomic %. Having improved toughness, this fine amorphous metal wire can be drawn or otherwise worked efficiently on an industrial scale with minimum breakage. In addition, this wire has good fatigue characteristics and high corrosion resistance, as well as high tensile breaking strengths, high heat resistance and superior electromagnetic performance. Therefore, the wire is very useful in a broad range of applications including a variety of mechanical members, industrial reinforcements, and electromagnetic materials.