Based on the 49-month wave data collected continually at the station of Gyanghai Bay, statistical analysis of wave characteristics was conducted. The results show that the wave height in the bay is usually below 0.5 m. The year-to-year variation of annual-average wave height is small, while the seasonal variation is quite notable. Both the year-to-year and seasonal variations of maximum wave height are prominent. Higher waves occur mainly in summer and autumn, due to tropical cyclones. During Typhoon Hagupit, the wave height increased rapidly, with the maximum wave height reaching 3.55 m. The pattern of typhoon wave was wind-driven wave pattern.