Cold-drawn pearlitic steel wires exhibit the highest strength amongst steel products for commercially use. The microstructure and the mechanical properties of wires are influenced by the drawing and post-drawing aging process. The transition of lamellar structure, e.g. cementite fragmentation, dissolution and re-precipitation, ferrite refinement, by drawing and recovery and recrystallisation by aging are summarised. In addition, the corresponding changes in mechanical properties, e.g. yield strength, delamination, hydrogen embrittlement and fatigue are summarised.