The concept of a space in contemporary architecture cannot be seen as being simply empty space, but it is the understanding that space has vitality. Because many architectural elements interact with each other, this allows other forms to be created or destroyed constantly in space. Therefore modern architectural forms need to be considered with the quality of a space. The meaning of the space in contemporary architecture is largely consisted of a phenomenological and topological thinking system. Therefore, this study is focused on the spatial understanding on operating the architectural diagram for constructing the spatial form. First of all, after understanding the thought of space in modern society, the method of diagram was classified into phenomenological and topological space construction. A way of classifying the phenomenological space construction can be subdivided into diagrams: human behavior, data, image, language for form construction and principle for form generation. Topological space construction can be classified into diagrams which have information processing and interpretation, organization, structure, sequence, and circulation. This study will provide a base for the right direction in practical use of diagram; when diagram is used for the construction of spatial form that has the space quality of modern society.