This article analyzes the relationship between Being and humanity in Martin Heidegger's "Letter on Humanism." It explores the philosophical foundations of his critique of traditional humanism, the specific understanding of human essence, and the role of language as a space for the revelation of Being. It demonstrates that humanity is viewed not as the center of existence, but as one called to preserve the truth of Being. Hermeneutic and comparative philosophical methods are employed. The results demonstrate the relevance of Heidegger's ideas for contemporary understanding of human identity and spiritual values in the context of global transformations. Keywords: Being, humanity, humanism, language, existence, Heidegger, philosophical anthropology.