Wave fields in the Bohai Sea are continuously simulated by the third-generation wave model SWAN in order to determine the wave energy resources from 1985 to 2010. The wind parameters used to simulate waves are obtained by the Regional Atmospheric Modeling System (RAMS). Comparisons of significant wave heights between simulations and observations show good agreement. The spatial distributions of mean monthly and annual averaged significant wave height and wave power flux are presented. Wave energy roses and temporal variations of average wave power density at five typical points in the Bohai Sea are calculated. Furthermore, the correlations between significant wave height and wave energy period are studied in scatter and energy diagrams.