A mathematical model of strain induced precipitation kinetics of Nb (CN) in HSLA steel has been established and the model gives accurate prediction when only a single deformation was given. In this work, the model is evaluated by employing roughing deformation at different strain before finishing at 900 C. The results in this way show that both roughing strain and temperature have a significant influenced on precipitation kinetics after finishing. As a roughing strain increaded, start time for 5% fraction precipitation is considerably accelerated and archieved a constant value when roughing strain was performed over 0.3.