The variables that are affecting the rate of work hardening tensile gain during wiredrawing were investigated. The study shows that the effect of Stelmor® cooling rate and laying head temperature and their interaction were significant factors causing the variation in wire tensile strength gain. The Stelmor cooling rate has the most significant effect on tensile gain among the three factors such as carbon percentage, Stelmor cooling rate and laying head temperature. There is a substantial increase in the dislocation densities in the wire rods and wires with an increase in the Stelmor cooling rate from 14°F/s to 26°F/s, which is the primary cause of the increase in the tensile strength gain. An increase in laying head temperature has very little effect in the wire tensile strength gain when the wire rod is cooled with a rate of 26°F/s.