To improve the utilization efficiency of sunlight, near-infrared (NIR)-responsive Gd3+-doped WS2 was prepared by a microwave-assisted solvothermal method. The microwave-assisted method required 1 h to synthesize the particles. To examine the activity of the photocatalyst under only NIR laser irradiation, its photocatalytic activities were evaluated by monitoring the degradation of Rhodamine B under 808 nm NIR laser irradiation. The NIR-responsive photocatalyst can also be used in the UV and visible light regions having shorter wavelengths than the NIR region. Photoactivity under a broader range of wavelengths can lead to more efficient photocatalytic reactions. Since NIR radiation has high permeability, the IR-photocatalytic reaction can be successfully carried out even on cloudy days or in damp environments. To prove this, the NIR laser was passed through a milk layer, following which a photocatalytic reaction experiment was conducted.