The invention discloses a piezoelectric type energy harvesting unit and an application thereof. The piezoelectric type energy harvesting unit is formed by installing a piezoelectric vibrator in a simply supported beam supporting structure. The piezoelectric type energy harvesting unit provided by the invention and a load circuit are serially connected to form a power supply unit; the power supplyunit is installed in constructions such as bridges, dams, buildings and the like, and vibration energy from the environment can be harvested to supply power for a wireless sensor node monitoring the fatigue status of buildings and/or mechanical equipment. A plurality of piezoelectric type energy harvesting units are combined to form a piezoelectric type energy harvesting module; the piezoelectrictype energy harvesting module can be laid in rooms, subway stations or squares with dense people, etc. like ordinary floor to convert energy generated by working people into electrical energy. The piezoelectric type energy harvesting module can be directly laid under concrete of pavements, railways or airports to convert vibration energy of road surfaces into electrical energy.