With the economic and social progress, people‘s demands for intelligent, miniaturized and portable electronic devices are more and more urgent, which have promoted the development of smart wearable devices and microelectronic systems. The power supply system is an important part of modern electronic equipment. Traditional batteries have shortcomings such as short battery life and heavy pollution. Therefore, it is urgent to find a green sustainable power supply for microelectronic devices. Compared with traditional nanogenerators, flexible nanogenerators have become current research hot spots due to their excellent flexibility, mechanical properties and processability, providing an important method and path for solving the current power supply requirements of wearable electronic devices. Among them, the self-powered mode nanogenerators of flexible piezoelectric and triboelectric have received widespread applications and attention in recent years. In this article, the research progress and working principles of piezoelectric, triboelectric and hybrid nanogenerators at home and abroad are reviewed, nanogenerators based on different materials, structures and application fields are expounded, and their applications in composite devices are summarized. The development trend of this field is summarized and prospected.