The technological system of cast iron and steel-making was established and consolidated during the Warring States Period, Qin and Han Dynasties. Iron-making refractory materials provided structural, chemical and thermal stabilities in the ancient cast iron and steel-making productions. However, compared with metal and slag research, there is a lack of research on refractory materials. We carried out a comprehensive study, based on literature and field investigations as well as scientific analyses, especially the petrographic analysis. According to the petrographic analysis, it is believed that 1) rammed clay or stacked clay bricks were used to build the furnaces in early imperial China and 2) the sand material was rarely used, and the composite materials of clay, sand and rock fragments were not presented yet. In addition, the microstructures of the furnace materials, casting moulds and tuyeres (furnace nozzle) were very different, which shows that craftsmen during this period could make different refractory materials according to different performance requirements for different components of the iron production process.