Desulphurizer is one of the key factors in the field of desulphurization technology In this paper, the influence of several additives on the desulphurization effect of calcium-based compounds and the mechanism were analyzed based on a lot of experiments Different kinds of sulfur-fixing agents based on CaCO 3 were prepared by inputing some single additive, some mixed additives and reformed by some chemical solutions The desulphurization rate of these agents was studied with ZCS-1 intelligent sulphur determination Some highly efficient agents and CaCO 3 were calcined, and their physical characteristic were studied with PoreMaster-60 mercury porosimeter Some reformed agents by some chemical solution after being added certain additives had better results at high temperature The sulfur-fixing efficiency of the best one could reach as high as 50% (Ca/S=1 5) at 1?100?℃ Its physical and sintered characteristic at high temperature were improved After reformed with aliphatic acid and being added some additives, the porosity of CaCO 3 increases from 15 57% to 34 93% while its surface area increases from 14 52?m 2/g to 19 94?m