Herein, it is revealed for the first time that oxidized detonation nanodiamonds (Ox‐DND) can produce hydrogen under solar irradiation without addition of cocatalyst or formation of heterojunction with another semiconductor. This hydrogen production is investigated using two sacrificial reagents and compared to the one of hydrogenated detonation nanodiamonds (H‐DND). The effect of the Ox‐DND and sacrificial reagent concentrations on the hydrogen production is also studied. At its maximum, a H$_2$ production yield of 32 μmol h$^{−1}$ is obtained for a Ox‐DND concentration of 12.5 μg mL$^{−1}$ (using only 1 vol% of triethanolamine as sacrificial reagent), similar to the one of TiO$_2$ nanoparticles tested at the same concentration in the same illumination conditions.