The aim of this study is to develop a seawater desalination system that uses sea-wave energy as the sole energy source for system operation. This system is composed of a sea-wave energy acquisition system, a reverse-osmosis device, and a proposed mechanism linking the system to function synchronously. The relationships between various system parameters and system characteristics are analyzed. The limitations and constraints of system operations are then suggested. For the purpose of comparison, another system, which indirectly drives the reverse-osmosis system through an additional stage of energy storage, is introduced. To analyze the system dynamic properties, the following steps are implemented. First, a mathematical model than can properly describe the system characteristics is derived. This model is found to be a nonlinear one, which increase the difficulties of system analysis enormously. However, it is also noted through a preliminary examination that the effect of system nonlinearity becomes insignificantly if the system parameters are properly adjusted. Under these parameters, the linearied model is analyzed. The effects of different system parameters on the amount of energy acquisition and desalinated water are investigated. The analysis indicates that the amount of energy acquisition or desalinated water is closely related to both the selected energy acquisition system and the desalination system. For a given energy acquisition system and sea wave condition, an improper system parameter selection of desalination system will either make the whole system operation inefficient or devastate the functioning of acquisition system. This suggests that certain parameters of the desalination system must be adjustable in a real operation. The study also shows that the linearied system can be approximated by a model with two degrees of freedom. This model may offer the convenience for the optimization of system parameters.