A piezoelectric linear actuator based on a double-acting plate stator structure is proposed to address the problem of small output power of existing single-plate piezoelectric actuators and to enrich the form of macro-micro linear actuators. The first-order longitudinal vibration and the second-order bending vibration of the double-acting plate are selected as the operating modes of the actuator, the longitudinal vibration is used to drive the mover to slide and the contact and separation between the driving foot and the mover is realized by the bending vibration. The process of driving the mover forward by the double-acting plate stator is explained and the elliptical trajectory equation of the driving foot and its ellipse forming conditions are derived. The structural dimensions of the stator are optimized to 45.3 mm×11.2 mm×6 mm and the simplification of the two operating modes is realized. An electro-mechanical coupling analysis model of the stator is established, the oscillations of the two-phase operating modes are solved. The frequencies of the two-phase modes are 34 994 Hz and 34 998 Hz respectively. The elliptical trajectory of the stator driving foot is simulated and the voltage regulating and frequency modulation characteristics of the stator are obtained. When the amplitude and frequency of the drive voltage are 250 V and 34 938 Hz, the amplitude of the driving foot along the x and z directions reaches 1.34 μm and 2.73 μm respectively, which is sufficient to drive the movers. The design of the assembly structure of the double-plate actuator has been completed and a three-dimensional assembly model is presented. The actuator is expected to output large speed and power, and has wide application prospects.