An automatic tube cap fitting set for pipe dust protection, characterized by including a tube handling system, a cap fitting set system, and a control system. The tube handling system comprises a frame and multiple tube handling wheel disks. The cap fitting set system is positioned on the side of the tube handling wheel disk on the frame and includes multiple radial positioners for pipes and cap fitting components. The cap fitting components consist of a cap component drive mechanism and a cap component positioning mechanism. The tube handling system and the cap fitting set system are controlled by the control system. The tube handling wheel disk rotates the pipe to the cap fitting position, the radial positioners for pipes radially restrict the pipe, and the cap component drive mechanism and the cap component positioning mechanism transmit and position the cap onto the pipe end for assembly.