Abstract: SO₂ is the main pollution gas that pollutes the atmosphere, endangers health and causes economic losses. It is also one of the main exhaust gases discharged from cement kilns and other large-scale industrial production processes, which seriously affects our lives. In the current desulphurization method, dry desulphurization has no waste slag wastewater generation, low heat loss, is conducive to energy saving and emission reduction, and is the most environmentally friendly method at present. In many dry desulphurization agents, calcium-based desulphurization agent has an important position because of its rich resources, and easy to use. Calcium-containing industrial waste slag was used in the preparation and modification of calcium-based desulfurizer to improve dry desulfurization performance due to its high calcium content or rich metal oxides and SiO₂. In this paper, the present research on the preparation of calcium-containing industrial waste slag and the modification of calcium base desulfurizer for dry desulphurization were reviewed, and the modification methods to improve the desulphurization performance of calcium-containing industrial waste slag were discussed by analyzing the modification mechanism and desulfurization reaction process.