Transform Domain Communication System (TDCS) is a new type of wireless communication system, which can actively avoid interference according to the change of external electromagnetic environment, and achieve RF stealth by using noise-like performance of basis function. The technologies of amplitude spectrum shaping and pseudorandom phase generating are the core technologies of TDCS. In this paper, the development process of TDCS is introduced with analysis to its principle and key technologies, and the problem existed in the actual military applications is presented. Finally, an outlook is made to the future development of TDCS according to the military needs and research progresses.