Slingshot effect (SE) and its significance with regard to ocean wave energy conversion is discussed. It is shown that owing to the huge inertia which can be transported by the ocean wave plus its periodicity, then a movable puck elastically colliding against a pusher plate driven by the oscillatory motion of the ocean wave can attains a great magnification in its kinetic energy which can be harnessed for electric generation. Because the oscillatory nature of the motion of the waves, the oceanic slingshot driven by the motion of a pusher plate Will be a stochastic process in which head-on collisions (gain in energy) between the wave and the movable puck and collisions when the wave is going away (loss of energy) occur. Nevertheless, it is shown that the result of this stochastic process is that head-on collisions are more frequent and as a result there will be a net gain in energy per collision. One interesting possibility is at what one could call a slingshot resonance where only head-on collision between the pusher wave and the puck are allowed by matching the travelling time of the puck with the period of the ocean wave.