Stochastic resonance is a physical phenomenon where large vibration occurs when a weak sinusoidal force is applied to a bi-stable system. It is expected larger vibration can be produced than a typical resonance. Then the authors utilize this system to an energy harvester, which generates energy from vibration. The energy balance between the generated energy and the energy consumed to produce the weak sinusoidal force is analyzed through numerical simulations. It is shown the proposed harvester generates more energy than the system using a typical resonance.