ZnS is a kind of material with superior optical, mechanical and thermal properties from visible light band to long-wave infrared band (i.e., 0.36-12 μm). It is widely used in infrared imaging, remote sensing, and guidance as well as other photoelectric systems. Also, ZnS is a semiconductor material with the widest band gap (3.6-3.9 eV) in the II-VI group compounds. ZnS materials can have superior luminescence properties by doping divalent transition metals (i.e., Co2+, Ni2+, Cr2+, and Fe2+). It is widely used in mid-infrared solid lasers, light-emitting diodes, radar screens and fluorescent lighting.Compared with ZnS single crystal, polycrystalline ZnS transparent ceramics can be used as main materials in commercial applications due to the advantages like short preparation cycle and easy preparation of coarse grain sizesas. The preparation methods of transparent ZnS ceramics mainly include hot pressing (HP), chemical vapor deposition (CVD), chemical vapor deposition combined with hot isostatic pressing (HIP), and spark plasma sintering (SPS). ZnS transparent ceramics prepared by different methods have certain optical and mechanical properties differences. The transmittance of ZnS ceramics prepared by HP in the visible light band is not as high as that of multi-spectral ZnS ceramics prepared by CVD and HIP post-treatment. However, the oriented grain size of multi-spectral ZnS ceramics is larger. The growth of grain size leads to a significant decrease in the mechanical properties, and the preparation cycle of CVD-prepared ceramics is also longer. Therefore, this review mainly represented development on the optical and mechanical properties of ZnS transparent ceramics prepared by different methods and introduced the application of ZnS transparent ceramics in infrared windows and mid-infrared lasers. In addition, the future development of ZnS transparent ceramics was also prospected.The physical and chemical properties of ZnS materials were described, including the phase structure, optical properties, and matrix characteristics of ZnS as a divalent transition metal (TM2+) doping. The main parameters of ZnS transparent ceramics prepared by different processes were summarized. The application scenarios of ZnS transparent ceramics in infrared window materials and mid-infrared lasers were described. The development of HP-ZnS transparent ceramics, CVD-ZnS transparent ceramics, and SPS-ZnS transparent ceramics applied in infrared windows were represented, and the preparation methods were briefly introduced. The preparation of ZnS transparent ceramics for mid-infrared lasers was introduced. The Cr2+ and Fe2+ doped ZnS transparent ceramics were discussed, and the spectral characteristics of two different ions in ZnS matrix were analyzed. The preparation of Cr2+/Fe2+:ZnS transparent ceramics were discussed. In addition, this review also prospected future development of ZnS transparent ceramics in different application fields.Summary and prospects:Although the long-wave infrared transmittance of HP-ZnS transparent ceramics is close to its theoretical value, the transmittance of its 1 064 nm laser band does not exceed 60%, which makes it difficult to realize the application in dual-mode guidance. Most of the HP-ZnS transparent ceramics still have a certain amount of hexagonal phase and impurities, leading to a decrease in the short-band transmittance of HP-ZnS transparent ceramics.Although the preparation process of CVD-ZnS transparent ceramics is relatively mature, which can be commercialized. The grain size of multi-spectral ZnS transparent ceramics increases to dozens of microns after HIP, resulting in low mechanical properties of the materials and poor corrosion resistance of multi-spectral ZnS.Most SPS-ZnS ceramics are still in the initial stage. Although SPS-ZnS ceramics have an advantage of maintaining small grain size, they have a low relative density and a poor long-wave transmittance of less than 70%.For ZnS transparent ceramics for mid-wave infrared laser, TM2+:II-VI can be mainly prepared by a thermal diffusion method. Cr:ZnS achieves a laser output, but Fe:ZnS does not achieve a laser output due to its low optical quality and lack of suitable pump source.Since the first semitransparent ZnS ceramic was prepared in the 1950s, ZnS transparent ceramics have been extensively studied in the past 70 years. With the increasing demand for infrared imagers and multi-spectral imagers in the fields of national defense, security, and civilian fields such as vehicle night vision systems, there is still a challenge for technological progress and development of ZnS transparent ceramics in the future. In terms of ZnS ceramics for infrared windows, it is necessary to continue to optimize the powder preparation process, improve the chemical purity and phase purity of the powders, and regulate the Zn/S value, combined with HP and HIP to prepare multi-band high-transparent ZnS transparent ceramics. In the future, the mechanical properties of multi-spectral ZnS transparent ceramics can be further improved by coating and other technologies, and its application range can be expanded. The further optimization of the preparation process of SPS-ZnS ceramics is needed. In terms of ZnS transparent ceramics for mid-infrared laser materials, the effective doping concentration and structural uniformity of active ions are improved without reducing the transmittance of the sample, and a further exploration is needed to prepare ZnS ceramics with a high power laser output.