A high-entropy oxide (HEO) of TiZrNbHfTaOₓ was synthesized using a mechano-thermal method for efficient photocatalytic hydrogen production. The HEO exhibited a bandgap of 2.45 eV, covering both UV and visible light regions, enabling hydrogen production from water under light without the need for a co-catalyst. Hydrogen production increased with exposure time, reaching 134.76 μmol/m²h after 3 hours. This HEO demonstrated superior performance compared to conventional photocatalysts like TiO₂, producing hydrogen without co-catalysts and showing long-term stability. The HEO's unique structure, achieved through a two-stage mechano-thermal process, allowed for uniform element distribution and fully oxidized cations, enhancing photocatalytic efficiency. The HEO's high surface area and mesoporous structure further improved its catalytic activity. This study highlights the potential of high-entropy photocatalysts for hydrogen production without the need for precious metal co-catalysts, offering a promising solution for sustainable energy. The synthesis method is simple and scalable, making it suitable for future research and applications in photocatalysis.A high-entropy oxide (HEO) of TiZrNbHfTaOₓ was synthesized using a mechano-thermal method for efficient photocatalytic hydrogen production. The HEO exhibited a bandgap of 2.45 eV, covering both UV and visible light regions, enabling hydrogen production from water under light without the need for a co-catalyst. Hydrogen production increased with exposure time, reaching 134.76 μmol/m²h after 3 hours. This HEO demonstrated superior performance compared to conventional photocatalysts like TiO₂, producing hydrogen without co-catalysts and showing long-term stability. The HEO's unique structure, achieved through a two-stage mechano-thermal process, allowed for uniform element distribution and fully oxidized cations, enhancing photocatalytic efficiency. The HEO's high surface area and mesoporous structure further improved its catalytic activity. This study highlights the potential of high-entropy photocatalysts for hydrogen production without the need for precious metal co-catalysts, offering a promising solution for sustainable energy. The synthesis method is simple and scalable, making it suitable for future research and applications in photocatalysis.