Deep space optical communication is the main technical approach of high speed data transmission to meet the future deep space exploration, and the main technical direction for the China Deep Space TT&C Network development. Especially with the development of intelligent and networked space communication system, the intelligent space communication network combining RF and optical communication will become the core facilities to support future deep space exploration missions. This paper combines China future lunar and deep space exploration development plan, based on the mission support capability of China Deep Space TT&C Network, the requirements of future deep space optical communication are sorted out. On the basis of learning from the latest research results, this paper analyzes the technical approach of constructing the earth terminal of deep space optical communication system. Based on the actual situation of China, this paper puts forward the development idea of constructing the mixed deep space optical communication ground system with space relay terminal and earth terminal, and finally forming the cognitive network of deep space optical communication.