The article raises the question of the relationship between humanistic and cosmic worldviews. The author examines the process of formation and development of the ideas of humanism and cosmism, paying attention to their relevance for modern society. Today, humanity, despite the high level of development of science and technology, the widespread dissemination of education and the solution of many problems that have threatened man for thousands of years of world history, still turns out to be incapable of truly implementing the main tenets of the humanistic worldview. Particular attention in the work is paid to the humanistic aspects of the philosophy of Russian cosmism, ideas expressed at the beginning of the twentieth century and remaining important ideological guidelines to the present day. The key idea of the cosmic worldview—the unity of man and the Universe, man and nature – is acquiring new meanings today. Environmental issues pose before humanity the task of harmonizing the relations between social and natural systems, which was also called for by representatives of the philosophy of Russian cosmism. The main sources of the research are the texts of Russian philosophers N.A. Berdyaev and K.E. Tsiolkovsky, the analysis of which allows us to identify the peculiarities of their ethical and social views, ideas about the transformation of society on a reasonable basis, based on the fact that the dissemination of knowledge and education are the main pillars of improving social and political orders. The author comes to the conclusion that such principles of a humanistic worldview as the inviolability of man and human life, respect for human dignity, preservation of individuality in the unity of the human race and the need for dialogue between different cultural communities are the key to the future existence and development of society, nature and the entire Universe.