Some animals and plants have special functions and structures. They are the result of biological evolution and Nature's ideas. The question to answer is how to use these biomimetic ideas to design the next generation of wave energy converters. In this paper, the characteristics of the existing wave energy converters are analyzed using biomimetic ideas and then the design rules hidden in them are established. First, the characteristics of wave energy are introduced. Next, the state of the art and methods of energy extraction by the wave energy converters are analyzed. Then based on the introduction of the biomimetic design knowledge, the biomimetic features, principles, and characteristics of the wave energy converters are explained. Lastly, the association rules hidden in the biological features and engineering features are mined based on the Apriori algorithm. These rules will assist the development of the next generation of biomimetic wave energy converters and provide future research trends.