The present invention provides a steel wire provided with stable workability performance. This steel wire is wire having a steel component containing, in mass%, C in the amount of 0.20-0.60%, Si in the amount of 0.15-0.30%, Mn in the amount of 0.25-0.60%, P in the amount of <=0.020%, and S in the amount of <=0.010%, with the remainder constituting Fe and inevitable impurities, the steel wire being characterized by having cementite as an internal structure, and in that 80% or more, in a unit number ratio, of the cementite in a cross-section perpendicular to the lengthwise direction of the wire has a minor axis of 0.1Mum or less, and an aspect ratio of the major axis to the minor axis of 2.0 or less.