The working principle of the Pelamis wave energy converter is described in this paper. The sectional size suitable for the outside sea of Xiamen Bay is redesigned according to the Froude and Strouhal similarity criteria. The swing angles, hydrodynamic coefficients, and wave exciting forces are calculated based on the AQWA hydrodynamic software and the average outside sea condition of Xiamen Bay. It is concluded that the Pelamis after redesigned by the Froude and Strouhal similarity criteria can run better in the outside sea area of Xiamen Bay. The three sections indirectly contacted with the fixed axis have larger swing angles. The wave period and height affect the speed ofthe response of the section and its swing angle range, respectively. The larger the total forces, the larger the swing angles. The wave circular frequency has a greater effect on the added mass and the wave exciting force than on the radiation damping; the heave added mass and the heave wave exciting force will become smaller when the heave radiation damping becomes larger with the increase of the wave circular frequency.