The WS2/MgAl-LDH composite was prepared by a two-step hydrothermal method. The analysis of X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscope, transmission electron microscope and X-ray photoelectron spectroscopy show that the WS2 nanoparticles are synthesized in situ between layers of MgAl-LDH. The composite was used as a catalyst to degrade 150 mg·L-1 methyl orange solution with pH value of 3.The results show that the degradation rate of methyl orange solution exceeds 80% under simulated visible light irradiation for 75 min, and the cycling performance is excellent. Therefore, WS2/MgAl-LDH composite is considered a promising photocatalyst.