The adsorption of hydrogen sulfide and sulfur dioxide on retorted oil shale is investigated for two different grades of oil shale that were retorted in a combustion retort. The adsorption studies were carried out in a packed bed arrangement at three different temperatures and consisted of six different concentrations of either hydrogen sulfide or sulfur dioxide in pure nitrogen. Equilibrium data were fitted to the Langmuir and Freundlich equations and a generalized three parameter equation proposed by Radke and Prausnitz. The isoteric heat of adsorption were calculated and compared to the heat of condensation for each of the adsorbents separately.