A process for capturing organometallic impurities comprising at least one of a heavy metal, silicon, phosphorus, and arsenic, contained in a hydrocarbon feed comprising contacting the feed with a capture mass comprising at least one of iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), lead (Pb) and zinc (Zn) deposited on a porous support at least one of aluminas, silica, silica-aluminas, and titanium, or magnesium oxides used alone or as a mixture with alumina or silica-alumina, the metallic element being in the sulphide form with a degree of sulphurization of at least 60%, and in which the feed to be treated is a catalytically cracked gasoline containing 5% to 60% by weight of olefins, 50 ppm to 6000 ppm by weight of sulphur and traces of arsenic in amounts in the range 10 ppb to 1000 ppb by weight.