A beam marking system is disclosed for marking on beams with a marking device. The beam marking system includes a beam marking device configured to mark on the surface of a beam. A movable arm is coupled to the marking device. The movable arm has at least three movable components that collectively move the beam marking device along or about at least three axes. A controller is in electronic communication with the movable arm and the marking device. The controller controlling the movement of the at least three movable components of the movable arm and controlling the operation of the marking device. In some instances, the beam marking system can automatically mark beams, such as metal beams used in heavy construction projects in a rapid and accurate manner.