Thermal activated sepiolite was prepared and used as an adsorbent for efficient decoloration of crude palm oil. The effects of activation temperature on the structure of sepiolite were investigated by Fourier transform infrared spectroscopy, X-ray fluorescence, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, Zeta potential and nitrogen adsorption–desorption isotherms techniques, and the decolorization efficiency for crude palm oil was systematically evaluated by Lovibond tone. The results indicate that the thermal activation of sepiolite affects its structure and decoloration efficiency. The Red value and content of phosphorus only reduced by 28.29 and 68.00 %, respectively, after decoloring with acid-treated sepiolite, but by 57.14 and 76.00 %, respectively, after thermal activation because that the thermal activation improved the porous structure and surface activity of sepiolite by releasing different kinds of waters and creating new adsorptive sites. In addition, the suitable activation temperature (400 ℃) is significant to reach an optimal decoloring capacity.