The Chengdu Plain was the iron production center in southwest China in the Han dynasty (202 BC-220 AD), which three iron smelting sites and large amounts of iron objects were excavated in the past decades. However, metallurgical studies of iron production in the Chengdu Plain have been overlooked for a long time. This paper provides an opportunity to understand the iron production technology in the Chengdu Plain in the Han dynasty. The metallurgical analyses of excavated iron objects from the Baozishan cemetery site show that most iron tools and weapons were forged from decarburized iron and fined iron. Besides, carburization, decarburization, and quenching techniques were used to control the malleability of iron objects. According to the results, the primary use of iron at Baozishan was forged wrought iron and steel, which evidenced that forging technique played an important role in the Chengdu Plain in the Han dynasty.