Abstract: In recent years,microwave measurement techniques based on Rydberg atom have been developed rapidly and widely used.The technology of detecting microwave based on coherent effect of Rydberg atom is novel that can directly correlate microwave field strength with frequency measurements via fundamental physical constants,with high sensitivity,large dynamic range,and low measurement uncertainty,it is expected to be the next generation of microwave electric field reference that can be traced directly to the International System of Units(SI).In this paper,the principle and development of microwave measurement based on the coherent effect of Rydberg atom are introduced in detail,the research progress at home and abroad is discussed in three aspects,including high accurate measurement，high sensitivity and microwave polarization direction measurement.In final,the applied research in engineering system has been discussed in three aspects,including the technology of addressing the broadband Rydberg states,the simulation analysis versus experiment test of vapor in microwave electric field and design of fiber-coupled vapor.

Key words: Rydberg atoms, Microwave electric field, Measurement sensitivity, Autler-Townes splitting(AT splitting)