In order to complete the reasonable plan of the design standard of marine engineering in extreme wave events, the joint distribution of annual extreme wave height and annual extreme period was constructed. Based on the SW model hind east wave model from 1996 to 2020 in Guangdong Sea Area, optimal marginal distributions of annual extreme wave height and annual extreme period at each location were obtained through the evaluation of the goodness-of-ft. And the joint distribution function of wave heights and periods was using the Archimedean Copula function to compare the different return periods and risk probably. The results show that there may be similar features in the joint wave height and period distribution in Guangdong Sea Area. Under the same design frequency, the concurrent return period is the largest, the secondary return period is the second and the joint return period is the smallest. The secondary return periods at different design frequency for the four representative sites in Guangdong sea area are 119.49–6.35a, 116.32–8.14a, 115.89–6.56a and 116.39-–9.61a. The design values of wave height and period of Guangdong sea area calculated by secondary return period can provide effective guidance for marine engineering construction standards.