The structural, electronic and thermodynamic properties of cubic double perovskite Ba2YTaO6 are calculated by using the plane wave within density functional theory (DFT) framework employing the generalized gradient approximation (GGA). The ground state quantities including the lattice parameter, bulk moduli and its pressure derivative are fitted by the Birch–Murnaghan equation of state. The calculated energy band indicates that Ba2YTaO6 has a direct band gap of 3.42 eV at [Formula: see text] point in the Brillouin zone and the energy band near Fermi level is determined by the density of states of O 2[Formula: see text], Ta 5[Formula: see text] and Y 4[Formula: see text] electrons. The thermodynamic properties including Debye temperature, bulk moduli and heat capacity of various pressures and temperatures are calculated and analyzed. Results indicate that the temperature and induced pressure have significant effect on the thermodynamic properties of Ba2YTaO6.