Contamination of Cr(VI) is of global concern, whereas the innovation in wastewater treatment is required. Combination of bentonite and cellulose could produce an effective adsorbent to treat Cr(VI)-containing wastewater. The aim of this study was to investigate the use of composite bentonite/cellulose (B/Cell) to remove Cr(VI) in the aqueous media, in which the bentonite was collected from local sources. The Na-bentonite was firstly prepared before proceeding to cellulose embedment. The resultant B/Cell was characterized for its functional groups, morphology, and crystallinity. The Cr(VI) adsorption capacity and removal efficiency were determined based on batch adsorption. Our findings revealed that the B/Cell composite with a 4:1 bentonite-to-cellulose mass ratio exhibited the highest removal efficiency (85.68%) among tested formulations. Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction analyses confirmed the successful integration of cellulose and structural modification of bentonite. Optimal adsorption was achieved at pH 3, 180-min contact time, and 10 g/L adsorbent dosage. Isotherm modeling showed excellent fits for Sips (R2 = 0.9992) model, with maximum adsorption capacity reaching 192.56 mg/g. Kinetic analysis indicated pseudo-second-order kinetics (R2 = 0.959, qe = 1.018 mg/g), suggesting a chemisorption mechanism. These results highlight the potential of the B/Cell composite as an efficient and low-cost adsorbent for Cr(VI) removal from aqueous environments.