Tensegrity systems have been used in several disciplines such as architecture, biology, aerospace, mechanics and robotics during the last fifty years. However, just a few references in literature have stated the possibility of using tensegrity systems in ocean or energy-related applications. This work addresses the kinematic and dynamic analyses of a planar tensegrity mechanism for ocean wave energy harvesting. A planar tensegrity mechanism is proposed based on a planar morphology known as "X-frame" that was developed by Kenneth Snelson in 1960s. A geometric approach is used to solve the forward and reverse displacement problems. The theory of screws is used to perform the forward and reverse velocity analyses of the device. The Lagrangian approach is used to deduce the equations of motion considering the interaction between the mechanism and a linear model of ocean waves. The result shows that tensegrity systems could play an important role in the expansion of clean energy technologies that help the world's sustainable development.