Barium indate (Ba2In2O5) is an interesting compound with potential applications as oxide-ion conductor, oxygen sensor, separation membrane and electrochemical device material. Information on thermodynamic stability of barium indate is essential for long term use of this compound under reactive chemical environments. The present paper deals with the detailed thermodynamic investigations on barium indate, Ba2In2O5. Standard molar enthalpy of formation of Ba2In2O5(s) at T = 298 K (ΔfH0298) has been determined employing an isoperibol solution calorimeter. The standard molar heat capacity (Cp0) of barium indate was derived from enthalpy increment data measured employing a high temperature calorimeter and the thermodynamic functions such as H0T - H0298, Cp0m, S0T, H0T , G0T - (G0T - H0298 /T, ΔfH0T and Δf G0T have been generated.