Abstract The highly successful generalized gradient approximations PBE-GGA and GGA+U were employed to study in addition to the crystal structure, the electronic, magnetic, and optical properties of the double perovskite material noted Ba2GdRuO6. For this purpose, the use of first principle calculation, which is considered a significant tool to investigate the properties of this kind of materials, could provide a better understanding of their possible potential applications. The stability of this new material of cubic form is validated by optimizing its structure, and tolerance factor. The electronic structure of Ba2GdRuO6 shows its semiconductor behavior, which provide band gaps energy values of 1.024 eV and 1.316 eV for both GGA and GGA+U approximations, respectively. The antiferromagnetic phase originated from the strong magnetization between the Gd-4 f and Ru-4d orbitals producing a magnetic moment equal to 3.99 µB. Furthermore, its optical properties exhibit a high optical conductivity of 105(W.cm)−1, an ideal band gap energy, high dielectric constants, and a strong light absorption coefficient in the visible and UV electromagnetic spectrum, making this newly designed material a promising candidate for high optoelectronic performance perovskite solar cells.