In this report, silver sulfide (Ag2S) was selected as a new H2S splitting photocatalyst material, and considered the synthesis method of Ag2S photocatalyst particles with stratified structure. Previous stratified particles were synthesized by using metal oxide (hydroxide) as the precursor. Ag2O particles as the precursor of Ag2S were synthesized by mixing AgNO3 solution and NaOH, and their particle sizes could be controlled by the solutions' concentration. Then, Ag2S particles were obtained by adding Na2S solution into suspending solution of Ag2O particles with optimum sizes. Particle sizes of Ag2S were changed by Na2S concentration control, and remaining Ag2O precursor could be dissolved by adding NH 3 solution. The photocatalytic H2S splitting could be realized by UV-light irradiation on the Ag2S particles without co-catalyst like Pt.