This article examines Yeats’s laughter which operates as an overtone, undercurrent, or a keynote throughout all his work. We discover that his comic aspects betray various meanings or nuances. First, the comic elements in Yeats are explosive in that they function as a means of disorienting and transgressing social regulations, and social categories like class, gender, race within a social system. Moreover, laughing escapes from and discards the established system at a burst as the disproportionate laughter of King Goll in “The Madness of King Goll.” Furthermore, Tom’s laugh in “Tom O’Roughley” concentrates itself on the aimless joy as Derrida says that laughing laughs at itself like a sovereign operation. Secondly, the laughing in Yeats is conveyed in the degradation of the dignified or exalted objects. Freud says that the increased expenditure of the solemn restraint discharges vacantly when it does not satisfy its higher purpose. Sometimes the lightest thing can acquire superiority over the weightiest by pulling down or aerification which makes the solemnity unable to retain its dignity. In “Crazy Jane Reproved,” Jane challenges the omnipotent God with such lighthearted refrain as fol de rol. The technique of pulling down applies to the depreciation of national monument or eternal art. Yeats knows well that Maud Gonne will be slighted by the coming generations and that the great Irish patriots, O’Donell, Emmet, and Parnell can also be mocked severely. Likewise the eternal art as the marble of Callimachus cannot avoid damages from weightless wind. Yet, for Yeats laughing is not always easy to express; he cannot release any laughter encountering with the same situation as effortless laughing was possible once. In “The Apparitions,” Yeats confesses that he required all his energies to disperse the fright of an apparition which he could easily have laughed at last time. On the other hand, there is an occasion in which the childish and vulgar comic changes to utter solemnity like a revolution. Yeats examines the transformation of the middle class carefully from indulging in silly talks to generating terrible beauty in “Easter 1916.” The trivial levity turns into the sublime inconceivably without intention. Lastly Yeats proposes a peculiar and paradoxical laughter which is difficult to vocalize as in “A Dialogue of Self and Soul.” This sort of laugh cannot surpass the burden of secular life, but great sweetness like Nietzsche’s tragic joy can break out even if the afflictions of human life make it distorted.