Zirconium dioxide and Aluminium oxide–40% Titanium dioxide thermal barrier coatings (TBCs) were deposited on Nickel based Inconel 625 superalloy with plasma spray process. The aim of the present study is to compare hot corrosion behaviour of ZrO2 and Al2O3-TiO2 plasma sprayed thermal barrier coatings on Nickel based Inconel 625 superalloy in air oxidation and in molten salt environment i.e K2SO4–60% NaCl environment at 800°C under cyclic conditions for 50 cycles. The thermo-gravimetric technique was used to establish the kinetics of corrosion. The corrosion products have been analyzed using the SEM and EDS analysis. Both coatings protect the underlying Inconel 625. The ZrO2 coating performed relatively better than Al2O3-TiO2 coating against hot corrosion in air and in the given environment. © 2014, Sphinx Knowledge House. All rights reserved.