Abstract: Medium and low grade magnesite is piled up because of the difficult in direct ultilization,while the preparation of high temperature desulfurizer is one of the effective ways for its resource utilization. The desulfurization performance of the calcined products under different calcination temperatures and calcination time were studied. The grain size,specific surface area and pore size of the products were characterized by XRD,SEM and BET,and the removal mechanism of H₂S was analyzed from the microscopic perspective. Under the conditions of calcination temperature of 750 ℃ and calcination time of 30 min,the specific surface area of calcination products can reach 168. 42 m² / g,the average pore size is 4. 44 nm,and the grain size is small (9. 10 nm). The calcination products obtained under these conditions were used for desulfurization. Under the adsorption temperature of 500 ℃ and the space speed of 7 200 h^-1,the H₂S penetration time was 162 min and the sulfur penetration capacity could reach 14. 75 mg / g. The results provide a new way for the resource utilization of medium and low grade magnesite.