To provide a method that can eliminate hydrogen sulfide contained in a biogas continuously and almost completely using the PSA-system by adsorption-regeneration.

The method comprises eliminating hydrogen sulfide from a biogas by contacting the biogas with a silica adsorbent having pores of a 1.00.5 nm pore diameter, and it is preferred that the silica adsorbent is the one synthesized without using any surfactant, at least 99.9 wt.% of its total amount comprises oxygen and silica, and total content of metallic impurities is not more than 50 ppm.