Gijang Sea is located on the southeastern coast of Korea. This study establishes a basic system to identify optimal sites for the wave power generation. To achieve this goal, the field measurements were made at the field site in front of Dong-am fishing port at Gijang. In addition, we analyzed the offshore wave data at the Donghae buoy operated by Korea Meteorological Administration(KMA) and compared the data with the wave characteristics in Gijang Sea. The main results were as follows. In winter, the wave direction in Gijang Sea ranged between east and south($90{sim}180^{circ}$). The main wave direction was east($90^{circ}$). The Significant wave heights and periods were under 2 m and $5{sim}15$ sec, respectively. A comparison of water depth and wave direction constitutes one(condition) of the important parameters for selecting the optimal site for the wave power generation.