SiO2 sol was used to enwrap the LaNi4.8Al0.2 alloy to improve the hydriding performance of the alloy. The samples after drying were analyzed by SEM. The effects of preparation parameters on hydriding performance were studied, which include water content, silica content, granularity of the alloy and the drying techniques. Results show that most metal particles are embedded into the silica sol. The sol viscosity is reduced gradually with more water and longer time. When the ratio of water to silica is 8:1, the hydriding speed of the samples is the fastest. The hydrogen absorption capacity per unit mass solid is increased with less LaNi4.8Al0.2 alloy. It is easier for the sol to enwrap the metal when the granularity of metal particles is smaller, and the hydriding performance of the samples is better. Furthermore, the hydrogen absorption capacity and absorption speed of the samples heated and dried in Ar is worse than that heated and dried in air. Thus the hydriding performance is not much relevant with the noble gas protection. The hydrogen absorption capacity and the absorption speed of the samples are obviously superior to that of the LaNi4.8Al0.2 alloy under 0.2 MPa hydrogen pressure.