The purpose of this study is to grasp musical expression in the Monastery of La Tourette, an architectural work produced by an architect, Le Corbusier and a musician, Iannis Xenakis based on a musical piece, Metastasis. The results of the study on musical expression in the Monastery of La Tourette, which was done through analysis of correlation in expression between architecture and music, and spatial characteristics of this monastery, are as follows: First, in modern architecture and music, the expression of the space-time continuum concept is emphasized. Second, the architectural characteristics in this monastery that constitute musical expression are the Modular, confliction and fluidity in composition, plastic (acoustic) shape and symbolic shape. Third, these architectural characteristics are found to be expressed as counterpoint, alteration, temporality, acoustics and canon of music.