The time intervals of the wave data by different wave observation methods are inconformity,and the accuracy of the data needs to be analyzed.Based on the annual wave observation data of hourly interval in Dacheng Bay,we obtain the wave data sets of different time intervals,apply statistical and correlation analysis methods to analyze the correlation of wave condition,wave height and wave period of large waves among different data sets.The results show that the wave condition of the data sets varies little,and the large wave height has a good correlation whose difference is 11.4%,while the large wave period has a poor correlation with 78.1% difference.Wave height data with a long time interval can be calculated by the correlation formula of this paper.It can provide more reliable wave height values for engineering applications in the situation of limited data.