An energy harvester for converting vibration energy into electrical energy and harvesting the electrical energy includes: a base; a clamping structure which is supported by the base and is spaced apart from the base; an elastic member which is disposed between the base and the clamping structure and allows the clamping structure to be elastically moved relative to the base; and a cantilever structure including a cantilever beam having one side fixed to the clamping structure and the other side which is elastically bendable, and a mass body disposed on the cantilever beam.