Abstract: The solvothermal method was used to prepare Fe₃O₄@C core-shell microspheres. The structure and morphology of the nanocomposite powders were characterized by X-ray diffraction, transmission electron microscopy, and Fourier transform infrared spectroscopy, and then the particles were used as heterogeneous catalysts in the UV-Fenton removal of VOCs in gas. The results show that the Fe₃O₄@C core-shell microspheres have a strong adsorption capacity for VOCs due to the outer layer of Fe₃O₄ being coated with a carbon layer of uniform thickness and pore structure. For sparingly soluble organic gases such as octane, the adsorption of these particles could increase the total concentration of VOCs in the liquid phase. Therefore, the opportunity for the Fenton reagent to be in contact with the VOCs gas increases, causing a significant improvement in the gas removal efficiency. Moreover, the cooperation factor β was introduced to evaluate the synergistic effects in the integrated process of the adsorption-catalytic oxidation by the core-shell structure particles.