The silicate-cement clinker was prepared by sulfuric acid leaching ferronickel slag, and the effects of various temperatures and limestone saturation coefficients on the structure and microscopic morphology of the clinker were investigated. The burnability of the cement clinker was judged by the determination of f-CaO content in the clinker, and the phase structure, elemental distribution and microscopic morphology of the clinker were analyzed by XRD, EDS and SEM. The results show that the higher the calcination temperature is, the lower the f-CaO concentration is, and the better the burnability is. When the sintering temperature is 1 350 ℃, the Portland cement clinker appears pulverization and does not form C3S phase after sintering. However, when the calcination temperature is 1 400 ℃, the crystal phase dominated by C2S and C3S appears in the Portland cement clinker, and pulverization not occurs. When the sintering temperature reaches 1 450 ℃, the cement phase grain structure is fully developed. After the clinker is mixed with gypsum to make cement, the compressive strength and flexural strength of the hydration products of cement mortar after 28 d curing are 37.34 and 7.01 MPa, respectively.