With the rapid development of new energy vehicles, gear transmission systems are facing increasingly stringent demands for high efficiency, low noise, high reliability, and performance under high-torque variable-load conditions. The design, manufacturing, and inspection technologies of gears are crucial to the reliability and safety of new energy vehicles. Firstly, this paper summarizes the influence of tooth flank modification on NVH (Noise, Vibration and Harshness) in gear transmission design for new energy vehicles. Secondly, the impact of grinding and power honing on gear manufacturing within the production technology of new energy vehicle gear transmissions is elaborated. Third, the application of optical inspection and deep learning in gear inspection technology for new energy vehicles is discussed. Finally, prospects for gear technology are provided, focusing on AI-driven design, multi-energy field hybrid manufacturing, and non-contact inspection technologies.