Abstract: It is well known that there are unique Zisha clay mineral resources in Yixing, China. However, until now, very few works have been reported on them and the corresponding sintering products. This is unfavorable to the protection and application of the Zisha clay mineral resources. Yixing Qingshui Zisha clay has been studied as an example. The composition of the Qingshui Zisha clay and the microstructures of the corresponding sintering products were analyzed by XRD, XRF, SEM, mercury porosimetry, and EDS. The results show that Qingshui Zisha clay is comprised of 57.0% quartz, 12.3% hematite, 14.3% kaolinite, 13.0% illite, and 3.4% montmorillonite, and the sintering Qingshui Zisha pottery has rich hierarchical pore structures. It is demonstrated that the microstructures of Zisha pottery result from a lack of liquid and the high content of Fe ions in liquid during the sintering of Qingshui Zisha clay. The study of formation mechanism of Zisha pore structures indicates the future application in porous ceramics of Yixing Zisha clay mineral resources.