This paper aims to clarify the diversity of open courtyards in faubourg Saint-Antoine area in Paris, by focusing on spatial composition and by analyzing the exterior space arrangement and the connection with the street and with the buildings. Firstly, the arrangement patterns are shown by analyzing the arrangement of the compositional units articulated by their surrounding buildings. Secondly, the connection patterns are described by analyzing the distributive role of the courtyard and the form of its connection with the street. Finally, by considering both of these patterns, 10 types of spatial compositions appear which show the diversity of the open courtyards. Then, comparing these types reveals their structural characteristics.