Abstract: Activated carbon flue gas injection is currently the main technology to control the concentration of heavy metals in incineration flue gas. However, the efficiency of the adsorption performance of activated carbon at high temperature (>150℃) is low. Therefore, the development of high-temperature resistant non-carbon-based adsorbents is of great significance to the control of heavy metals in high temperature flue gas. Sulfur-doped boron nitride (S-BN) is a non-carbon-based high-temperature resistant heavy metal adsorbent used for high-temperature adsorption of gaseous heavy metals. In this study, boric acid and melamine were used as precursor materials, thiourea was used as sulfur source to be doped into the precursor, and S-BN adsorbent was prepared by high temperature diffusion. The results showed that the surface of S-BN had a rib-like structures and the internal pore structure was obvious. The morphology and structure of S-BN varied with the molar ratio of S doping. It was found that S-BN was a typical mesoporous porous adsorbent, and its internal pore volume, pore size distribution, and average pore size were 0.17-0.39 cm³/g, 0.85-284.39 nm, and 2.95-4.19 nm, respectively. The maximum specific surface area of the adsorbent obtained after pyrolysis at 1300℃ for 5 h was 524.17 m²/g, and the molar ratio of S doping was 0.50. It was also found that 150-200℃ was the optimal temperature range for S-BN to control the adsorption of gaseous heavy metals. The adsorption rate was relatively faster in the first 5 min of the adsorption process, and the adsorption saturation could be basically reached within 10 min. Finally, it was found that the adsorption mechanism at low temperature was dominated by physical adsorption. With the increase of temperature, the adsorption mechanism changed from physical adsorption to chemical adsorption. The study has shown that the new S-BN adsorbent prepared in this experiment has a higher specific surface area. Its saturated adsorption capacity for heavy metals in gas phase was 54.15-74.13 mg/g. Compared with activated carbon, the adsorption capacity of Zn was 1.9-10.0 times., and it still has good performance at relatively high temperature (300℃).