Removing H 2S from biogas that is produced from anaerobic diges tion of palm oil mill effluent is a crucial step in order for the biogas to be utilized as a source of energy. In this study , palm shell activated carbon (PSAC) prepared by st eam activation was used to adsorb H 2S from simulated biogas. The parameters studied wer e H 2S concentration, adsorption temperature and space v elocity. The effect of these parameters towards breakthrough ads orption capacity was studied using statistical anal ysis with Design Expert Software. H 2S concentration and space velocity were found to be significant in affecting the breakthrough adsorpti on capacity.Adsorption temperature on its own was foun d not to have significant effect on the breakthroug h adsorption capacity but its interaction with other parameters was found to be sCharacterization of fresh and spent PSA C confirmed and provided further information on the adsorption of sulfur spe cies on PSAC pore surface.