In the talk the extremely complex challenges for Ukrainian universities caused by russia’s full-scale military invasion of Ukraine, which is now in its second year, are explored. A special emphasis is made on the internationalization as an integral part of Ukrainian university activities in time of war, a tool for its responses to challenges and crisis phenomena. The main responses of the higher education system of Ukraine to military challenges, namely improvement of online education, experience of displacement HEIs, support from the state, support of international institutions, programs with partner universities, are discussed. Personal experience of the practical implementation of the results of the internationalization of higher education, namely joint global classrooms and visiting lectures, as well as research results, which include a survey of university students about their studies during the war, are presented. It is discussed the measures to minimize the consequences of the destructive influence of russia’s military aggression on the educational process, to ensure quality education, to restore and create new educational and scientific partnerships and to ensure further development of professional and personal skills of students, necessary for raising national economy and civil society in the post-war period.