Terahertz technology has great potential application; terahertz wave has broad\|band which isn’t occupied. It has following features: higher data transfer rate，good direction, higher safety, lower scatter, higher transmittance and so on. Terahertz technology is becoming a research focus in communication field in developed countries. The paper introduces several key technologies and analyses latest achievement, basing on the framework of terahertz communication. At the same time, the paper foretells developing trend and application prospect and put forward the terahertz development strategy.