Water pollution by organic dyes has become a reason for environmental pollution and has been hostile to the aquatic ecosystem and this waste water needs treatment. In this study, unsupported NiO and kaolin-supported NiO composites were synthesized by one step wet impregnation-precipitation method through the precipitation of nickel hydroxide onto locally accessible, cheap, and easily treated kaolin surfaces by using sodium hydroxide as a precipitating agent. The product was calcined at 500℃ and used for the catalytic degradation of methylene blue (MB) dye in aqueous solution. The morphology, structure, and interaction of the synthesized materials were investigated by SEM, XRD, and FTIR spectroscopy, respectively. Characterization results showed the fabrication of NiO and the growth of NiO on the kaolin surface. To know the catalytic oxidative degradation performance of the catalyst, a lot of experiments were performed using MB dye as a model dye. The catalytic degradation tests confirmed the importance of NiO and the high catalytic activities of the synthesized NiO/kaolin composite toward MB dye degradation. The oxidative degradation result shows that the optimized precursor amount on the kaolin surface could efficiently enhance the removal of MB dye. The kinetic investigation of the catalytic MB dye degradation has fitted the pseudo-first-order kinetic model. More than 90% removal efficiency was observed after eight reuse cycles, proving exceptional stability and reusability of the composite. The catalytic process also proceeds with a low activation energy of 30.5 kJ/mol. In conclusion, the NiO-supported kaolin composite was found to be a favourable catalyst for the excellent catalytic activity to degrade a model dye MB from the aqueous solution in the presence of cheap and easily available NaOCl with catalytic efficiency of material by 20.3 mg catalyst higher than 99% within 6 min and an apparent rate constant, kapp, higher than 0.44625 min−1, far better than unsupported catalyst which has kapp of 0.0926 min-1 by 10mg dose in 20 minutes. The catalyst also applied to spiked real sample and shows good removal capacity.