Abstract: In order to avoid the presence of several guided wave modes at particular frequencies, the process of designing and fabricating PVDF comb transducer was discussed in detail. Experiments were conducted with a PVDF comb transducer mounted on a thin steel plate. The results showed that a single guided wave mode was achieved by a PVDF comb transducer in a controlled frequency. The application of PVDF comb transducer in fouling detection on the thin steel plate was also discussed.