In this study, Al-pillared white bentonite (Ordu-Unye, Turkey) was used for cottonseed oil bleaching. Pillaring process parameters were optimized in terms of bleaching efficiency as the bleaching capacity of cottonseed oil. The initial cation concentration, hydrolyzing agent ratio, and thermal treatment temperature were chosen as major process parameters. Pillared clays were characterized by FTIR and differential thermal analysis. The bleaching efficiency of bentonite increased from 11.8 to 17.5% by acid activation and to 33.5% by further A pillaring. The optimal pillaring process conditions for cottonseed bleaching were an initial concentration of AlCl3 of 0.5 M, a OH-/Al3+, molar ratio of 0.3, and a thermal treatment temperature of 700 degrees C.