The prediction of converted energy by one way gears wave energy converter may be influenced by non-linearity properties of the ocean waves. To date there has not been an adequate analytical model to predict the power production of one way gear wave energy converter under irregular wave condition. In this work, analytical model is developed to describe the interaction of one way gear wave energy converter that utilized gravity force of the gravityweight (M) with irregular ocean waves using JONSWAP (Joint North Sea Wave Project) model. This interaction model has been simulated numerically by means of computer software. The simulation result showed that wave height is strongly determining the converted output power. The outcome of harnessing the gravity force instead of buoyant force of this proposed model that commonly used by the previous wave energy converter demonstrate significant potential output power. The proposed model can be used to design feasible and efficient wave energy converter.