NOVELTY - Preparing desulfurizer comprises grain or active carbon as a carrier, where the preparation comprises (i) pickling the carrier active carbon, (ii) washing the carrier active carbon till the active carbon turns neutral, (iii) soaking the active carbon in halogen ion-containing aqueous solution, (iv) drying the carrier active carbon to remove moisture, (v) dipping or spraying the carrier active carbon using a solution with compound containing copper to make the compound containing copper load on the active carbon to obtain a catalyst precursor which is dried and baked to obtain the product.    USE - The method is useful for removing hydrogen sulfide from natural gas.    ADVANTAGE - The desulfurizer has high hydrogen sulfide removing capacity and high purity. The raw materials adopted by the method are readily available, so environmentally-friendly treatment is easy.    DETAILED DESCRIPTION - Preparing desulfurizer comprises grain or active carbon as a carrier, where the preparation comprises (i) pickling the carrier active carbon, where the acid concentration of the pickle liquor is 0.1-5 N and the acid is hydrochloric acid or nitric acid or phosphoric acid, (ii) washing the carrier active carbon till the active carbon turns neutral and drying, (iii) soaking the active carbon in halogen ion containing aqueous solution to infiltrate the active carbon, where the halogen ion concentration of the soaking solution is 0.01-0.5 N, the amount of the soaking solution is 0.1-3 times the absorption capacity of the active carbon and the soaking time is 2-24 hours, (iv) drying the active carbon to remove moisture and (v) dipping or spraying the carrier active carbon using a solution with a compound containing copper to make the compound containing copper load on the active carbon to obtain a catalyst precursor and drying the catalyst precursor for 2-6 hours under 100-120 degrees C in air after being aged and baked for 2-4 hours to obtain the desulfurizing agent under 300-400 degrees C under inert gas atmosphere.