Abstract: Nondestructive testing (NDT) plays an important role in welding quality inspection of steel structures. The nondestructive testing methods such as ultrasonic testing and magnetic powder testing belong to inspecting after welding, whereas the visual inspection of groove gap, welding current, electrode status can control the welding quality at the source. This paper calls on the peer to pay attention to the role of visual inspection, and strengthen the application of visual inspection in order to promote its development.