Under the influence of γ-quanta ( 60 Co, P=9.276 rad/sec, T=300K,) the amount, formation rate and radiation-chemical yield of molecular hydrogen obtained from the radiolysis process that changes the mass of water (m=0.00010.8 g) have been defined in the created nano-SiO 2 /H 2 O system with m=0.2 g mass and d=20 nm particle size. It was determined that the radiation-chemical yield of molecular hydrogen obtained from the water radiolysis process in the nano-SiO 2 /H 2 O system created by the adsorption of water on the nanoparticle surface had a low value. In systems created with the addition of water, the radiation-chemical yield of molecular hydrogen obtained from its radiolysis increased in direct proportion to the water mass. This proves that due to ionizing rays, the yield of electrons emitted from the nanoparticle surface into the water and solvated there increases. Therefore, the radiation-chemical yield of molecular hydrogen is higher than that of the adsorbed system.