We report a study on the synthesis of anatase titania (TiO2) particles with the sol–gel method at room temperature. We immobilized the particles on a grafted-cellulose intercalated montmorillonite (MMT). This nanocomposite, cellulose-g-poly(4-vinyl pyridine)/MMT/TiO2, could be applied in the photocatalytic degradation of organic pollutants efficiently because of the addition of a sorbent, the grafted cellulose. The synthesized nanocomposite was characterized with Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Methyl orange was used as a model molecule to study photocatalytic degradation. The nanocomposite exhibited a better photocatalytic activity than in the absence of the grafted cellulose. The kinetics of the photocatalytic degradation could be described by pseudo-first-order rate law.