Blade vibration parameters are crucial for influencing the operational efficiency and safety of major rotating equipment such as aero?engines and gas turbines. The blade vibration measurement method based on blade tip timing has become a standard technology for monitoring the health status of rotating blades. This article introduces the principle of blade tip timing measurement, describes the typical structure of the system and common measurement processes, and summarizes four key technologies of blade tip timing measurement, including high?precision extraction of blade arrival time, high signal?to?noise ratio blade vibration displacement measurement, extremely under?sampled blade vibration parameter identification, and blade fault diagnosis based on small?sample tip timing signals. It analyzes in detail the significant progress made in blade tip timing measurement methods in terms of blade tip timing sensing technology, vibration parameter identification technology, and blade fault diagnosis technology. It proposes the development trend and prospects of blade tip timing technology, and summarizes the future key research directions in the field of non?contact blade vibration measurement from four aspects: sensing signal multiplexing, uncertainty analysis and calibration, on?board application of systems, digital twin and intelligent operation and maintenance. It is expected to provide important references for the scientific development and engineering application of blade tip timing measurement technology.