Abstract: According to characteristics of gas shielded flux-cored arc welding, combined with the relevant standards of China and the development status of boiler manufacturing industry, the feasibility of adopting gas shielded flux-cored arc welding were analyzed and discussed for various common structures of boiler, such as large pipe joint, ear plate and container’s small pipe joint, through the welding test of simulated parts. The results showed that welding quality and performance could be guaranteed by gas shielded flux-cored arc welding for large pipe joint and ear plate structure. However, the defects such as slag inclusion, incomplete fusion and incomplete penetration were easy to produce by manual operation of gas shielded flux-cored arc welding for small pipe joint structure. When gas shielded flux-cored arc welding was adopted for important parts in boiler manufacturing, the volume type nondestructive testing should be carried out for the welded joints to ensure that there were no defects in welded joints of products.