Harvesting energy from biomechanical motion of a human poses a promising replacement for batteries in a modern day where portable devices ran out of batteries much faster than before. We developed an energy harvesting device that is focused on heel strike of a gait cycle. The device works by converting the vertical motion of a heel strike to a rotational motion that would generate power from an AC motor. AC motor was used instead of DC because of its capability to generate power in two directions. To further increase the power generation, spur gears were attached to the device as to amplify the rotational motion with a ratio of 27.5:1. The device managed to generate a power of 1.1W throughout a gait cycle. Biomechanical energy harvesting proved to be capable of storing powers in exchange of putting an extra effort and discomfort to the user while wearing it. Nevertheless, future versions of energy harvester should pose no problems and is a promising source of energy to power up portable modern gadgets such as cell phones and mp3 players.