The article describes the phenomena of communication between space crews and the Mission Control Center studied within the framework of the “Content” space experiment. The experiment was conducted with participation of Russian cosmonauts during ISS-43/44 - ISS-54/55 missions, and a specially developed method of content analysis of crew-to-ground communication was used. It was shown, for instance, that the structure of communication varied significantly depending on the degree of the cosmonauts’ workload and stress-related psychological tension. The main objective of our work presented in this article was discussion of the relationship of the psychological state of cosmonauts, studied on the basis of crew communication content analysis, with their need for social psychological support. The ideas about social psychological support in the context of crew - Mission Control Center (MCC) communication are outlined. Relevant practical recommendations are presented for modifying the communication style of the MCC personnel to psychologically support the crews. The principles and recommendations for effective communication will both provide continuous psychological support to the space crews in orbit and reduce the likelihood of emotional burnout among MCC personnel.