An object transport system is an essential device in the factory automation system (FAS). Generally, an object transport system is driven by a conveyor belt system or a magnetic levitation system. However, contact force in the conventional transport system can damage precision optical components, while the magnetic field can destroy the inner structure of the semiconductor. The ultrasonic transport system transports objects on an elastic body using an ultrasonic wave. When an ultrasonic wave is applied to a flexural beam, the flexural beam vibrates to excite the air layer, which lifts up the object on the beam to transport. In this paper, the dynamic characteristics of the ultrasonic transport system are theoretically analyzed. Through normal mode expansion, the modeling equation for steady state response of ultrasonic vibration is expressed and the natural frequency of the flexural beam in each mode is also estimated by using the finite element method (FEM).