Background. In the conditions of an Arctic expedition, people’s physical and mental health are affected not only by extreme climatic and geographical factors, but also by social and living conditions caused by group isolation. Comfort psychological atmosphere in an isolated team, its group cohesion and motivation are an environmental resource for expedition participants and contribute to maintaining optimal functional state throughout the entire shift period.The aim of the work. To identify and to describe group cohesion, group motivation and psychological atmosphere in the team as the parameters of group dynamics of "Arctic Floating University – 2023" expedition participants in connection with changes in their functional state during the shift period.Methods. We used V.A. Rozanova’s "Group motivation", C.E. Seashore’s "Group Cohesion Index", and A.F. Fiedler’s "Team’s psychological atmosphere" questionnaires; psychophysiological testing on the UPFT-1/30 "Psychophysiologist" device (variational cardiologic intervalometry, complex eye-hand reaction); M. Lüscher color test; statistical methods: descriptive statistics and correlation analysis using the Spearman coefficient. Follow-up monitoring of the functional state and group dynamics parameters of the expedition participants was carried out once every two days during the entire expedition period. 42 participants of the "Arctic Floating University – 2023" project took part in the study.Results. The functional state of the participants in the maritime Arctic expedition during the entire expedition period was characterized by acceptable and nearoptimal values, a sufficient level of performance efficiency, an average level of physical condition, the absence of signs of severe stress, and an average level of subjective comfort. Group cohesion, group motivation, and the psychological atmosphere in the team increase from the beginning to the end of the expedition period, and on the days 21–22, they have the highest levels compared to all days of the expedition. Mostly direct correlations were revealed between group processes and changes in the functional state of expedition participants.Conclusion. A positive relationship was established between group cohesion, group motivation and psychological atmosphere in the team and the parameters of the functional state of the expedition participants.