<p>In this study, the phase and structure evolution mechanism for calcium sintering of iron-rich zinc-bearing spinel-(Zn,Fe)Fe₂O₄ was clarified toward resource recycling of steel dusts. The evolution was first analyzed by thermodynamic calculations, and then a series of sintering experiments were carried out by controlling variables, including CaO concentration, sintering temperature, and sintering time. The results showed that the increase of CaO concentration facilitated the break-up of spinel structure and the separation of Zn and Fe elements; and the increase of sintering temperature and time enhanced the formation of calcium ferrites. Further analysis revealed the specific phase evolution during sintering involved multiple steps with regard to both gas–solid and solid–solid reactions. The spinel structure was first decomposed by a combined effect of high temperature and CaO, forming ZnFe₂O₄ and Fe₃O₄ spinels. Then, Fe₃O₄ was easily oxidized to Fe₂O₃, while ZnFe₂O₄ could be decomposed into ZnO and Fe₂O₃. The initially formed Fe₂O₃ subsequently reacted with CaO to produce two types of calcium ferrites. Moreover, the first Fe₂O₃ involved in the reaction could mainly come from Fe₃O₄, since this gas–solid reaction was much faster than the solid–solid reaction. Accordingly, the target regulation of phase evolutions during calcium sintering of (Zn,Fe)Fe₂O₄ spinel was discussed for efficient separation of Zn and Fe within spinel and further Zn recycling from steel dusts.</p>