Clays are the most utilized minerals and considered very efficient and economical sorbents according to their chemical and physical properties. Clays are enjoying rapid popularity in the petroleum refining industry for the various processes such as adsorption and separation. Removal of many components such as sulfur, heavy metals, colors and separation of different hydrocarbon groups of crude oil and petroleum fractions can be carried out by clay adsorption. The present review summarizes the using of clay as adsorbent in several petroleum refining processes such as desulphurization, deasphalting, waste oil recovery, bleaching, corrosion reduction, heavy metals removal and other. One of the simplest, easiest and efficient separation processes used in different industries is adsorption. Review results show that different types of clay are obtainable and used in many applications. Clay adsorption can be enhanced the treatment and finishing of crude oils and petroleum fractions through several modifications such as metals impregnation, acid and thermal activations. Bentonite clays promote the highest adsorption capacity to remove sulfur and a high bleaching potential. Attapulgite clay is effective in decolorization and neutralization any petroleum oil. Impregnation of NiO nanoparticles into kaolin improves the asphaltenes adsorption. Several modified as well as unmodified clays promote the highest removal efficiency of Ni and V from crude oil. Additionally, the adsorption pre-treatment affects the reduction in corrosion yields and the corrosion rate.