Electrochemical Impedance Spectroscopy (EIS) has been used to study the performance of two water base modified vinyl acrylic copolymer emulsions (rust eliminators) on rusted carbon steel in aqueous sodium chloride solutions. The coated (150-200 m thickness) samples were exposed to 100, 500, 1000 and 5000 ppm Cl-concentrations at 30oC, 50o and 80oC. These samples were immersed in the test solutions for about 200 hours while AC impedance measurements were carried out at fmed intervals and data were stored for analysis. Different types of plots, eg, Bode plot and Nyquist plot, were used for computing the values of different circuit components (Resistance, Constant Phase Element-CPE etc.) by using a non-linear least square fitting method program. The effect of chloride ion concentration and temperature on such coatings has been discussed in detail. It has been found that these coatings are not sufficiently protective for application on immersed steel structures in saline environments.