This article offers an extended comparative study of the poetry of Kumaran Aasan  and John Keats with particular emphasis on the theme of transience and the fragile nature of mortal existence. Through sustained close readings of five major poems by each poet—especially Aasan’s The Fallen Flower and Keats’s Ode on a Grecian Urn—the paper examines how impermanence, mortality, and aesthetic longing shape poetic vision. Drawing upon Romantic aesthetics, phenomenology, and cross-cultural literary theory, the study demonstrates that while Keats seeks to counter mortality through art’s promise of permanence, Aasan embraces impermanence as an ethical and philosophical truth grounded in natural cycles. Despite cultural and linguistic differences, both poets converge in their insight that the fleeting nature of life intensifies beauty, emotion, and meaning.