Abstract: The lifting mechanism of a crane requires sensors to monitor its motion parameters. Currently, sensors are mainly powered by power sources or batteries, which have problems such as wiring difficulties and inability to provide continuous power supply (battery-powered). Therefore, this paper studies a bidirectional energy harvesting triboelectric nanogenerator (TENG) with self-powered sensing function, which completes the capture of natural wind energy and the potential energy of heavy objects descending while monitoring the rotating speed of the drum of the lifting mechanism. Based on the working principle of TENG, a bidirectional energy harvesting TENG structure is designed, and a prototype with self-powered sensing function is developed. According to the actual working environment of the lifting mechanism, an experimental test system is built to conduct output performance, sensing, and application demonstrations. The research results show that the TENG can simultaneously collect wind energy in the environment and the potential energy of heavy objects descending in the lifting mechanism. The bidirectional energy harvesting mechanism can significantly improve the output performance by 40% compared with the unidirectional energy harvesting. Meanwhile, the motion state of the lifting mechanism is monitored by collecting and analyzing the output electrical signals, and the monitoring error of the rotating speed of the drum of the lifting mechanism is less than 1%. This work expands the research of TENG in energy harvesting and self-powered sensing, providing a new solution for monitoring the motion state of lifting mechanisms.