An automatic loading and unloading processing system includes a material storage assembly to store workpieces; a positioning device on a worktable; and a transport mechanism to transport the workpiece from the material storage assembly to the positioning device and transport the processed workpiece into the material storage assembly. The material storage assembly includes a material tray; fixing bases; a motion mechanism; and holders on the fixing base for fixing the workpiece, and the motion mechanism controls the movement of the material tray. The transport mechanism includes an auxiliary loading and unloading system arranged at a worktable to grab the holders and move horizontally; and a main loading and unloading system arranged on a main spindle to grab the holders and move vertically.