Abstract:Hancheng Zhichuan ancient iron smelting site is located at Zhixi village, Zhichuan town, Hancheng, Weinan city, Shaanxi province, the remains cover an area of over 4 000 m2, and archaeologically dated to the Western Han Dynasty. The research team carries out archaeometallurgical field investigation on the site and collects smelting relics such as slag and ceramic shatter. Composition analysis and microstructure observation of the 18 smelting relics were carried out using SEM and SEM-EDS, and optical micrographs. The experimental results show that 16 slag samples are high-calcium and low-iron slag of Si-Ca-Al system, the matrix is mainly glassy phase, occasionally fayalite, which should be cast iron smelting slag. One slag sample is high iron slag, mainly consisting of wüstite, and with a little fayalite and glass; another sample is metal block that microstructure is wrought iron, which these two samples may be likely the relics of puddling steel. This site is mainly a cast iron smelting site and also carries out the production activities of puddling steel, which is the earliest site of puddling steel production found in the Weinan area, Shaanxi province.