In this paper, we will study the locomotion behaviour of a meso scale legged piezoelectric mobile robot driven by standing wave. The design exploits the use of standing waves to be transmitted to its legs to propel the robot forward. A piezoelectric robot is designed and discussion are provided regarding the dynamic modelling of the mobile robot. An experimental measure of the speed according to the applied voltage is given herein on acrylic substrate. We have shown that 50 mm by 10 mm piezo actuator have demonstrated a bi-directional walking speed on acrylic substrate of up to 4 cm/s when a 40 V voltage is applied.