Abstract: Triboelectric nanogenerator (TENG) is an electronic device, that exchanges mechanical energy into electrical energy. TENG has presented a wide range of potential applications, such as blue energy harvesting, micro/nano energy sources, and self-powered sensing, owing to abundant material, simple structures, and ease of integration. However, enhancing the output performance of TENG has remained a focal point of scientific interest. Hence, insulting many studies, this work has analyzed the influence of triboelectric materials, friction layer structures, and device structures on TENG output performance according to the working principle of TENG. Meanwhile, the enhancement strategies of TENG output performance are summarized. Finally, the future development of TENG is concluded.