AISI 1020 steel is used in case hardened condition for simple structural applications. AISI 1045 is widely used for industrial applications requiring wear resistance and high strength. AISI 4340 alloy steel is mainly used in power transmission gears, shafts, and aircraft landing gears. Annealing, normalizing and quenching heat treatment was carried out on these steel grades. The metallography of these heat treated samples to reveal microstructural details was conducted. The electrochemical techniques were used to evaluate the corrosion behavior as a function of heat treatment procedure and microstructural details. Corrosion potential and Potentiodynamic polarization technique was used to investigate corrosion tendency and kinetic behavior of heat treated samples in saline solution. It was deduced that corrosion rate was decreased sequentially after quenching than annealing and normalizing.