We investigate the nonlinear electromechanical response of piezoelectric laminated actuators under alternating current (ac) electric fields both analytically and experimentally. A laminated beam theory solution is developed for the cantilever piezoelectric/metal/piezoelectric actuator, and the effects of ac electric fields on the deflection are analyzed. A simple phenomenological model of a vibrating domain wall in electric fields is used, and the macroscopic actuator response is predicted. A nonlinear three-dimensional finite element model is also developed. Bending tests are used to validate the predictions using bimorph-type bending actuators made with soft lead zirconate titanate (PZT) layers and a metal sheet. Theoretical predictions of the dynamic bending behavior are in excellent agreement with measured values.