Long term wave measurement is of vital importance for assessing the wave power resources, optimizing the productivity of wave energy devices, and determining the largest waves for the survivability of the wave energy device during its life time in sea. Among the technologies developed for measuring ocean waves, wave buoys may be one of the most popular used devices for long-term wave measurement. In order to investigate whether the wave characteristics can be accurately measured using the wave buoys, an experimental study was carried out on the performance of three wave buoy models, that is, Wavescan buoys and one ODAS buoy, in a wave tank using the European FP7-MARINET facilities. The wave measurements using the wave buoys are compared to the measured waves using the reference wave gauges in the tank so the accuracy of the wave measurements can be examined. This paper presents the analyzed results in both time and frequency domains and the comparison between the measurements by the wave buoys and wave gauges. The analysis results reveal that the wave buoys are reliable for measuring the scaled wave conditions, for both regular and irregular. Besides, the Wavescan buoys have better performances than the ODAS buoy in terms of accuracy and the correlation with the wave gauges.