Semiconductor pigment of Cd-Zn-S is synthesized through the solid state reaction method and its structure and surface morphology is characterized by X-ray diffraction (XRD) and scanning electron microscope(SEM). It is demonstrated that the crystal lattice of the product is hexagonal. When the heat treatment temperature increases, the distortion of crystal lattice reduces. The samples annealed at different temperatures agglomerate to different degrees while the one annealed at higher temperature agglomerates clearly. The infrared emissivity of Cd-Zn-S at two window-bands of 3-5 μm and 8-14 μm is researched. The researched result shows that the infrared emissivity of Cd-Zn-S in 8-14 μm wave bands is much higher than that in 3-5 μm wave bands. The infrared emissivity decreases with the increasing of heat treatment temperature, which reason is that with the increasing of temperature, the infrared absorption decreases and the scatter by the particles rises.