The experimental work deals with the effect of heat treatment on the corrosion behaviour of spring steels. In this study the heat treatments like hardening, normalizing and tempering were done for spring steels to obtain martensitic matrix, pearlitic structure and tempered martensitic matrix respectively. After heat treatment the microstructural studies were carried out for the samples using SEM. Hardness measurements were done. The corrosion behaviour of all heat treated samples in HCl at different concentration (1.5N, 2N and 2.5N) was determined using Tafel extrapolation technique. The variation in the corrosion rates due to the effect of heat treatment was noted. The results indicate that for fully martensitic matrix the corrosion rate is minimum and for pearlitic structure its maximum. As tempering time is increased the corrosion rate increases correspondingly. The corroded microstructural images were also taken using SEM and analysed.