Specific properties of bentonite clay have made them a valuable material in different process industries. Easy availability, low price and their effectiveness are the major factors which made fuller's earth, an adsorbent in cooking oil manufacturing industry. Textural characteristics of fuller's earth play an important role in its performance. These characteristics can be modified by treatment with organic acids, which is the safest method for enhancing the properties of fuller's earth. Major motivation of this research is to increase the adsorption capacity of fuller's earth by modification in its properties by organic acid treatment. Organic acid treatment assures the safety of equipment and safety of the labor as well. Four organic acids are used which are recommended best for activation. These acids are acetic acid, phosphoric acid, citric acid and oxalic acid. Clay is treated with all of these four acids and the acid which generates more active sites in clay is the best recommended acid for activation.