Abstract: Gears are key fundamental components for transmitting motion and torque, and their high-efficiency precision machining technology and machine tools directly determine the performance and reliability of high-end equipment. The escalating demands for transmission systems in sectors such as aerospace, new energy vehicles, and precision instruments are driving gears toward higher precision, lower noise, and longer service life. This evolution is propelling advances in precision gear machining technologies and imposing more stringent requirements on the geometric accuracy, dynamic stiffness, and thermal stability of machine tools. Gears are classified into cylindrical gears, bevel gears, non-circular gears, face gears, and other types by shape, while face gears have been applied in Apache helicopters but have no practical applications in China's helicopter transmission systems. Research status of precision machining methods and machine tools for cylindrical gears, bevel gears, and face gears is systematically reviewed and summarized both domestically and internationally. Prospects are provided in terms of forward design of machine tools, intelligent error compensation for machine tools, high-performance gear manufacturing methods, and gear design software, offering theoretical and technical guidance for subsequent research on gear precision machining technology and machine tools.