Long-term observations and data analysis of the Earth's middle and upper atmosphere, an important region for studying atmospheric processes and even climate change for studying human activities and climate change, are still insufficient. Terahertz limb-sounding technology can obtain atmospheric profiles all day and near all weather with high vertical resolution (approximately 1~5 km) and is particularly sensitive to some of the halogen gases associated with ozone depletion, making it an important method for measuring the Earth's middle and upper atmospheric parameters. The basic principles and advantages of terahertz limb sounding are summarized, the basic framework of the terahertz radiometer is introduced, the development of terahertz limb sounding technology domestically and internationally in the past three decades is discussed, the latest research status is reviewed, the future development direction is discussed, and terahertz limb sounding technology is summarized and outlooked to provide a reference basis for related research.