The invention aims to provide an improved device for marking a two-dimensional code on an outer ring. A conveyor belt for conveying from front to back is arranged in the middle of the top part of a working table; an installation base is arranged in the middle of the left side of the working table; a lifting plate is arranged on the top part of the installation base; a lifting motor is arranged inthe installation base; the lifting plate is connected onto the lifting motor; an installation frame is arranged on the right side of the top part of the lifting plate; a movable shaft is arranged on the top part of the installation frame; a horizontal connecting plate covers the outside of the movable shaft; a push-up air cylinder is arranged at the left end of the top part of the lifting plate; the left end of the connecting plate is connected with the top part of the push-up air cylinder; and a laser marking machine is connected to the right end of the connecting plate and is located above the left side of the conveyor belt. The laser marking machine is arranged above the left side of the conveyor belt so as to be used for marking the two-dimensional code on the outer ring, the laser marking machine is connected to the right side of the connecting plate, and the push-up air cylinder upwards pushes the connecting plate, so that a marking angle of the laser marking machine can be adjusted; and through arranging the lifting motor, the height of the laser marking machine can be adjusted, so that the device is flexible to operate and high in adaptability.