This study is about a relationship of architecture and polyphony music. In the field of interior architecture, there have been many tries of applying characteristics of music, such as abstraction and nature of time for users of space to have new experience. It has been possible because architecture and music have similarities in many ways. Regarding using proportional characteristic in architecture and music, the both fields are enormously related in some ways. The purpose of this study is explaining of possibility of architectural expression in music and suggesting a way of analysing architectural design based on musical elements emphasizing proportional characteristic. Therefore, it is going to analyse Counterpoint of Bach, which is well expressed in music and compare it with proportional characteristic of space through this study.