The method of increasing the end output displacement and force by applying axial compressive force to the cantilever piezoelectric bimorph end was studied in this paper. The FEM analysis was carried out, the elastic analytical solution and the modal equations were deduced, demonstrating a good coincidence between them. The result shows that under 120 V and 5.5 N axial forces, a 0.25 N ending block force and a 5 mm ending free displacement which is 3 times bigger than the original bimorph are obtained. However, the first nature frequency displays accelerated decreasing as the axial force increasing, When the axial force reaching the first order buckling load, the first nature frequency tends to be 0, and when it is 70% of the first order buckling force, the nature frequency still can be 45 Hz, which is a great advantage over the conventional servo actuator. Therefore, this actuator can improve the stability and controllability of micro air vehicle (MAV) effectively.