The invention relates to an anti-shake internal expanding fixture which comprises a fixture body connected with the spindle of a numerical control machine tool, a movable connecting sleeve, a fixed core spindle and an expanding sleeve which are arranged inside the fixture body, and a pop rivet connected with the movable connecting sleeve and the expanding sleeve. The anti-shake internal expanding fixture is characterized in that a centrifugal pressing claw mechanism is sleeved on the fixture body; the centrifugal pressing claw mechanism consists of a support fixed on the fixture body, a bracket, a spring connected with the support and the bracket, a balance block arranged at one end of the bracket, and a pressing claw arranged at the other end of the bracket; and the pressing claw can be fastened to the side end of a workpiece. According to the centrifugal pressing claw mechanism, the pressing force of the pressing claw on the workpiece at different rotating speeds is changed by utilizing the centrifugal force generated by the balance block which is rotationally driven by the spindle of the machine tool, so that the shake of the workpiece is avoided, the product yield is improved, and the machining efficiency of the product is improved.