The tuyere is an important item of equipment for a blast furnace. However, the tuyere life of the large blast furnace can be quite short. The failure of tuyere will seriously affect the production of a blast furnace. So, it is of great significance to carry out experimental research on any damaged tuyere with a view to extending its service life. The damaged tuyere from a 5800m 3 blast furnace in China was analyzed by SEM, EDS and optical microscope. According to the results of microscopic phase analysis, the tuyere failure types are defined and classified. It is found that the tuyere failure types of the large blast furnace are mainly divided into four categories: erosion, pitting, cracking and bending. The high-temperature slag-iron repeatedly bonding and peeling off from the tuyere is the main cause of tuyere damage. Finally, the failure mechanism of different types of damaged tuyere is analyzed.