With the increasing utilization of portable electronic devices and wearable technologies, the field of human motion energy harvesting has gained significant attention. These devices have the potential to efficiently convert the mechanical energy generated by human motion into electrical energy, enabling a continuous power supply for low-power devices. This paper provides an overview of the fundamental principles underlying various energy harvesting modes, including friction-based, electromagnetic, and piezoelectric mechanisms, and categorizes existing energy harvesting devices accordingly. Furthermore, this study conducts a comprehensive analysis of key techniques in energy harvesting, such as mode selection, efficiency enhancement, miniaturized design of devices, and evaluation of energy harvesting experiments. It also compares the distinct characteristics of different energy harvesting modes. Finally, the paper summarizes the challenges faced by these devices in terms of integrating human biomechanics, achieving higher energy harvesting efficiencies, facilitating micro-miniaturization, enabling composite designs, and exploring broader applications. Moreover, it offers insights into the future development of human motion energy harvesting technology, laying a theoretical framework and providing a reference for future research endeavors in this field.