Terahertz technology is known as “one of the top ten technologies to change the future world”, which is of great significance to basic scientific research, national economic development and national defense construction, especially in the future 6G communication. Terahertz source is essential to terahertz technology research and the core component of terahertz application system. In recent years, Resonant Tunneling Diode(RTD) terahertz source has attracted extensive attention because of its small volume, light weight, easy integration, room temperature operation and low power consumption, which opens up a new way for the popularization and application of terahertz. Through literature analysis, this paper reviews the development of RTD terahertz oscillators based on InP and GaN from the aspects of device material technology, main processes and device properties. At present, how to prepare high-performance, mature and stable InP and GaN based RTD terahertz oscillators has always been a research direction.