The invention relates to a wing flutter and vortex-induced vibration coupled and tunable piezoelectric energy harvester, belongs to the technical field of air flow-induced vibration energy harvesting,and solves the problems that an existing energy harvester is suitable for a single wind speed, low in harvested energy and difficult to popularize and apply. One ends of plate springs are connected with fixed supports, and the other ends of the plate springs are adjustably connected with one ends of the supports, so that the effective working length can be adjusted; the other ends of the supportsare provided with an elastic shaft, and the windward side of a wing is adjustably connected with the supports through the elastic shaft, so that an aerodynamic force and a torque transmitted to the plate springs by the wing are changed; the tail edge of the wing is provided with a cantilever beam; the free end of the cantilever beam is connected with a pin fin; and the two plate springs and the cantilever beam are provided with piezoelectric plates. According to the energy harvester, the effective working length of the plate springs and the mounting positions of the elastic shaft and the wingcan be arbitrarily adjusted, the flutter generation conditions of the wing are changed, and the vortex-induced vibration generated by the pin fin is coupled, so that the energy harvesting performanceand efficiency are improved; and the energy harvester can be widely applied to the air flow-induced vibration energy harvesting in a micro-wing type aircraft or a complicated and changeable wind field.