<p>Sulfur is one of the main impurities in iron ores which should be removed due to its harmful effect on steel production. In this study, a facile method for improving iron ore desulfurization at low temperatures based on microwave roasting has been proposed. It was shown that the typical iron sulfide in iron ore, pyrrhotite (Fe₇S₈), exhibited a relatively strong microwave response by determining its electromagnetic properties and microwave heating behavior. Under microwave irradiation, Fe₇S₈ in the iron ore could decompose quickly to produce SO₂ and sulfate. After microwave roasting at only 350&#xa0;°C, the contents of total sulfur (TS) and SO₄^2- in the iron ore were 0.79 wt.% and 2.13 wt.%, respectively, indicating the considerable decomposition of Fe₇S₈. After water leaching at room temperature, most of the sulfur in the roasted ore was removed due to the high water solubility of magnesium sulfate (MgSO₄). Consequently, an upgraded leaching product with a desulfurization percentage of 92.81% was obtained using the microwave roasting–water leaching process, showing a significant improvement of 72.10% compared with the conventional process.</p>