An inchworm piezoelectric linear actuator based on the principle of screw clamp is designed to achieve large thrust and large stroke. The principle of screw clamp movement is described and the overall structure design of the actuator is carried out. The influence of the clamp force on the end surface is analyzed through ANSYS finite element simulation and the strength of the torque motor shaft is checked. The matching relationship between the torque motor and the driving frequency of the piezoelectric stack is analyzed and calculated. Finally, an experimental test system was built and the experiment on the piezoelectric actuator was carried out. The results show that the actuator achieves a maximum thrust of 190 N and a stroke of 60 mm at a stack driving voltage of 150 V, a frequency of 100 Hz, and a motor speed of 150 r/min.