In this study，the siliceous refractories were prepared with tridymite and α-quartz，with the α-quartz phase contents of 0.4%，1.0%，2.0%，3.0%，4.0%，5.0%，6.0%，respectively. The contents of α-quartz phase were analyzed by X-ray diffraction (XRD)，and the working curve was drawn according to the linear relationship of diffraction intensity and the content of α-quartz phase. With the curve，the contents of α-quartz phase in siliceous refractories can be accurately and quantitatively analyzed.