A thin strip of thermoplastic polyurethane (PU) was found to bend to the cathode side under the application of a DC electric field. As the field was reversed, the bending went to the anode side at first and then switched back to the cathode side. The mechanism responsible for this bending and switching phenomena was investigated by means of monitoring the charging and discharging current during the application of electric field. It was found that the bending direction and magnitude can be correlated to the direction and magnitude of current flow. A detailed analysis of the current response shows that it is most likely a space charge limited current. A model based on a charge accumulation at the sample surface will also be presented in this paper. It can explain the bending as well as switching effect of the PU film. In order to visualize the charge contents in the PU film, we apply the thermally stimulated discharge current (TSDC) technique for the measurement. Our preliminary result has confirmed the existence of charged layers at the surfaces of the PU film.