Nd2O3 nanoparticles (NPs) at various contents as efficient cocatalysts were incorporated onto mesoporous LaNaTaO3 through a modified sol-gel approach for H2 evolution. The results indicated that both LaNaTaO3 and 0.6 %Nd2O3/LaNaTaO3 samples exhibited a reversible type IV adsorption isotherms characteristic for mesopores structure with large surface area around 260 m2 g–1. TEM image of Nd2O3 and LaNaTaO3 are highly dispersed with uniform semi-spherical morphology with particle size around 5 nm and 10 nm, respectively. H2 evolution over mesoporous LaNaTaO3 nanocomposite was estimated to be 1 μmolg−1; however, with boosting Nd2O3 contents from 0 to 0.6 %, the H2 evolution was increased from 1 to 1755 μmolg−1 in aqueous glycerol solution as the sacrificial reagent, it then became steady with increasing Nd2O3 above 0.6 %. The mesoporous Nd2O3/LaNaTaO3 exhibited the photocatalytic efficiency for H2 evolution 1750 times higher than LaNaTaO3. H2 evolution rate over mesoporous 0.6 %Nd2O3/LaNaTaO3 nanocomposite was greater 1420 times than that mesoporous LaNaTaO3. Photoluminescence the photoelectrochemical studies proved that the best condition amount of Nd2O3 NPs, found to be 0.6 %Nd2O3/LaNaTaO3, efficiently prohibits the photoinduced charge carriers recombination rate. It was interesting to conclude that the enhancement of photocatalytic efficiency was significantly based on the incorporation Nd2O3 NPs onto mesoporous LaNaTaO3.