The rock-based sea area has great prospect of development and construction of offshore wind farms (OWFs), and the mainstream construction sites of OWFs in China have shifted from the soil-based seabed to the rock-based seabed area. Previous studies about mechanical properties of seabed materials and bearing characteristics of pile foundation in OWF mainly focus on the submarine soil-based seabed, resulting in lack of direct reference for the construction of offshore wind power in the rock seabed. Therefore, the study concentrates on the investigation of failure criterion of submarine completely weathered granite (CWG) of offshore wind farms in rockbased sea area under cyclic loads. Firstly, dynamic triaxial tests are carried out, and two unique development modes of CWG are revealed under different cyclic loads. The experiments analyze insight stiffness attenuation law and establish the prediction model of stiffness attenuation based on the logarithm formula. More critical, a unique development law of damping ratio of submarine seabed materials is discovered and discussed, and two cyclic failure criteria based on cumulative strain and dissipated energy are put forward to divide the critical CSR under cyclic loads, which gives helpful reference for the construction of offshore wind farms in rock-based sea area.