This study intends to demonstrate how Seamus Heaney devotes himself to excess and examines how his devotion leads to his poetics as a unique metaphor, focusing on his sexuality poems. Heaney’s sexuality poems put a meaningful perspective on humans and their lives. Heaney treats sexuality as a way of devoting himself to his excessive self-consciousness and details in his poems. The unexpected combination of ‘sexuality,’ ‘excess,’ ‘devotion’ gives Heaney’s poetry unusual energy. Heaney’s early works talk about juvenile sexuality with his overflowing sense of language, while later ones make use of it as a unique way in the process of building his poetics. In order to give a concentrative consideration to his sexuality poems, this study aims to investigate how Heaney’s eroticism is shown in his poetry, and then mention his ‘reticence’ poetics described in his The Government of the Tongue and The Redress of Poetry. In considering the process of according apparent controversial ‘excess’ with ‘reticence’ and pursuing his own poetics, this study aims to shed a new light on Heaney’s poetry and poetics as a whole.