Abstract:Terahertz technology is playing an important role in many fields,such as physics,chemistry,astronomy,medical science,material science and environment science due to its unique characteristics.It has also boosted the progress of national economics,national security and new informational science.The Terahertz detector is a key aspect of terahertz technology.In this article,the principles and applications of terahertz detectors are introduced,and the developing trend is discussed.